Ampicillin

aminopenicillin (beta-lactam antibacterial)

Also sold as Principen, Penbritin.

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Findings for this medication

Research about this medication, graded for how strongly each finding can be attributed to it. Nothing here describes your own levels.

Ampicillin has almost no classical depletion machinery. It is "excreted largely unchanged in the urine" with probenecid delaying that excretion [1][3]; about 20% of a 250 to 500 mg dose is metabolized in healthy subjects, to penicilloic acids, and no metabolizing enzyme is named in the record read [5]. No CYP450 inhibition or induction is stated in any label text read [1][2][3]. The mechanisms that apply are the ones the drug is built to produce or that follow from its salt form and its route into the gut: antibacterial action on commensal bacteria (it appears in bile and undergoes enterohepatic circulation [6]), the sodium in ampicillin sodium (2.9 mEq or 66 mg per gram [1][2]), and, for oral use, reduced absorption with food [3][6][8].

aminopenicillin (beta-lactam antibacterial) · ATC J01CA01 (WHO ATC/DDD Index [4]) · also sold as Principen and others; original brand Penbritin (Wikipedia and Tier D [7]) · reviewed 2026-10-09. This describes research about the medication. It does not say anything about your own levels or health.

How to read the evidence grades

These colours describe how strongly a finding can be attributed to the medication in the research. They are not a severity score and they say nothing about your own health.

Grades describe how strongly a finding can be attributed to Ampicillin in the research — not how common it is, how serious it would be, and not anything about you personally.

Red — Severe: Two or more independent Tier A sources, this drug in the cohort, the nutrient directly measured, consistent direction, clinically meaningful magnitude, a named mechanism, no substantial contradicting Tier A evidence.
Orange — Moderate: At least one Tier A source with this drug in the cohort showing a real but bounded deficit: an exposure window, a subgroup, low frequency, or a functional rather than circulating deficit.
Yellow — Low: Mechanistic plausibility only (Tier B), or class extrapolation (Tier C) with no drug-specific human status data; also used for context flags and interactions running the other direction.
Not graded — disclosed evidence gap: Nothing has been measured here, so this finding cannot be graded. That does not establish either safety or harm, and it is not the same as a White result.Source definition: Not gradeable under the rules above because nothing has been measured. Published as a documented gap, never as reassurance that there is no effect.

What the research found

Sodium: label sodium load of ampicillin sodium (excess/retention direction); a pooled burn-unit cohort shows a small serum sodium rise; ampicillin not separable

Yellow — Low

See study details

Ampicillin for injection carries 2.9 mEq (about 66 mg) of sodium per gram, and in a burn-unit cohort a high-sodium antibiotic group that included ampicillin-sulbactam had serum sodium rise by about 2 mmol/L, but no ampicillin-specific sodium result exists.

Full detail and limits

What the grade means here: Mechanistic plausibility only (Tier B), or class extrapolation (Tier C) with no drug-specific human status data; also used for context flags and interactions running the other direction. Yellow

Limits on what this shows

Null findings: None located for ampicillin sodium specifically. The injection label records doses of 2 g daily for many weeks "without adverse reactions" [2], a statement about adverse reactions generally, not about sodium.
At-risk subgroups: Not defined for ampicillin from the sources read. The burn cohort found a larger rise with more burned surface area [27]. Heart failure, renal impairment and neonates are conventional sodium-load concerns but no ampicillin-specific source was read for them.

Direction

EXCESS / RETENTION risk (sodium load), the opposite of a depletion. Supplementation or added dietary sodium would be the hazard, not the remedy (Hard Rule 5).

Regulatory status

Injection labels: "Ampicillin for Injection, USP contains 2.9 milliequivalents of sodium (66 mg of sodium) per 1 gram of drug" [2]; "65.8 mg [2.9 mEq] sodium per gram ampicillin" [1]. No sodium restriction warning, hypernatremia or potassium statement appears in the text read [1][2]. The capsule label states no sodium content (sodium lauryl sulfate is an inactive ingredient only) [3]. By multiplication (reviewer arithmetic), the WHO parenteral defined daily dose of 6 g [4] carries about 17 mEq or 396 mg of sodium.

Population evidence

Bamberg 2024 [27] (Tier A for a pooled exposure; retrospective, single German burn center, 120 adults with large burns; abstract read through a PubMed summarizer): antibiotics were classed as high-sodium (ampicillin/sulbactam, cefazolin, piperacillin/tazobactam) or low-sodium (meropenem, vancomycin). Serum sodium rose by 2.1 mmol/L (SD 4.18) on day 1 and 2.44 (SD 5.26) on day 2 in the high-sodium group (n = 64; both p Ryu 2026 [26] (240 adults on piperacillin-tazobactam or ampicillin-sulbactam; 29.6% had a sodium, potassium, chloride, calcium or phosphate abnormality) combines all electrolytes and does not report by drug in the abstract.

Mechanism

Named by the authors and by the label figure: the sodium contained in the salt form of the injection [27][1][2].

Cohort test

Ampicillin-sulbactam was in the Bamberg cohort but pooled with two other drugs; ampicillin alone was in no sodium study. Not class extrapolation, but not isolable either. Capped at yellow.

Counter-evidence held on record

Counter-evidence and confounding The burn-unit sodium rise coincides with fluid resuscitation and evaporative water loss, and the high-sodium group was not randomized. A rise of about 2 mmol/L is small relative to the SD. Near-orange candidate: an ampicillin-stratified serum sodium result would be needed. Framing caution Excess/retention risk, not a deficiency. Nothing here supports changing sodium intake, and no sodium or other supplement is recommended. Sodium handling in heart failure, kidney disease or neonates belongs to the prescriber.

Potassium: serum potassium fell by a mean of 0.28 mEq/L with ampicillin-sulbactam in a matched hospital cohort; combination and active-comparator design; disturbance, not dietary depletion

Yellow — Low

See study details

In 59 matched hospitalized adults given ampicillin-sulbactam, serum potassium fell by a mean of 0.28 mEq/L and 25.4% developed hypokalemia, similar to piperacillin-tazobactam, but there was no unexposed comparator and the product contains sulbactam.

Full detail and limits

Limits on what this shows

Null findings: The comparator was a drug already reported to lower potassium, so the similar result does not show a difference from piperacillin-tazobactam but also does not test either against no antibiotic. No ampicillin-alone potassium study was found; the PubMed listing "ampicillin hypokalemia" returned 36 records; the first 10 included this cohort and the Ryu study, piperacillin-tazobactam reports, Listeria meningitis series in which ampicillin was treatment, and older combination-therapy papers, with no ampicillin-alone hypokalemia report (listing lines only) [37].
At-risk subgroups: Lower baseline potassium, longer therapy and female sex in the matched cohort [25].

Direction

DISTURBANCE (lowered serum potassium during IV therapy, presumably a renal-handling effect that was not characterized in the sources read). It is not dietary depletion and does not imply that potassium intake should increase (Hard Rule 5).

Regulatory status

Hypokalemia and potassium are not mentioned in the injection or capsule label text read [1][2][3].

Population evidence

Tashiro 2025 [25] (Tier A for ampicillin-sulbactam; retrospective propensity-matched cohort, 2020 to 2022, Oita University Hospital, 59 patients per group, ampicillin-sulbactam versus piperacillin-tazobactam; abstract via an OpenAlex reconstruction): mean serum potassium change -0.28 +/- 0.47 mEq/L versus -0.35 +/- 0.51 (P = 0.443); percentage decrease 10.7 +/- 7.0% versus 11.0 +/- 9.7% (P = 0.822); hypokalemia incidence 25.4% versus 27.1% (P = 1.000). Risk factors for a fall were baseline potassium, duration of therapy and female sex. No confidence intervals are in the abstract. Ryu 2026 [26]: combined electrolyte outcome in 240 adults, not reported by drug in the abstract.

Mechanism

A named mechanism was not retrieved in the sources read.

Cohort test

Ampicillin IS in the cohort but only as ampicillin-sulbactam (combination with a beta-lactamase inhibitor); the analysis cannot attribute the change to ampicillin rather than to sulbactam, illness or concomitant drugs. Capped at yellow.

Counter-evidence held on record

Counter-evidence and confounding Hospitalized patients have many reasons for falling potassium (illness, fluids, diuretics, diarrhea). Confounding by indication is presumed until excluded (Hard Rule 6). Near-orange candidate: an unexposed or ampicillin-alone comparison with a confidence interval would raise this. Framing caution A monitoring prompt for high-dose or prolonged IV therapy, not a reason to take potassium. Potassium supplements carry their own risks and no dose is recommended here.

Vitamin K and bleeding: bleeding time lengthened in two neonatal ampicillin cohorts (a platelet-function outcome); vitamin K never measured; no ampicillin INR signal on the labels read

Yellow — Low

See study details

IV ampicillin prolonged bleeding time in two small neonatal cohorts after about 3 to 4 doses (NICU) and after 10 or more doses (very low birth weight), but no study measured vitamin K, PIVKA or prothrombin in ampicillin users, and the NIH vitamin K sheet does not name ampicillin.

Full detail and limits

Limits on what this shows

Null findings: The PubMed listing "ampicillin hypoprothrombinemia vitamin K bleeding" returned three records (a cefazolin case report; cefoperazone and mezlocillin in cancer patients; a tobramycin trial with cefoperazone or mezlocillin), none with ampicillin (listing lines only) [37]. No vitamin K, PIVKA or menaquinone measurement in ampicillin users was found.
At-risk subgroups: Neonates in the first week, particularly very low birth weight infants with longer courses [21][22].

Direction

Drug effect on bleeding (platelet function) and a proposed gut-flora route to lower vitamin K. Not a vitamin K deficiency: bleeding time is an outcome measure and vitamin K was not measured (Hard Rule 2).

Regulatory status

Neither the injection labels nor the capsule label returned an oral anticoagulant, INR or prothrombin statement for ampicillin; thrombocytopenia and thrombocytopenic purpura are listed hematologic reactions [1][2][3]. Vitamin K is not mentioned in the label text read.

Population evidence

Sheffield 2010 [21] (Tier A for the bleeding-time outcome; 15 NICU patients, gestation 33 to 41 weeks, IV ampicillin 50 to 100 mg/kg every 12 hours, mothers without beta-lactam in labor; abstract via a PubMed summarizer): baseline bleeding time 134 s (95% CI 120 to 148); no increase after the first dose (n = 5); after the third (n = 5) and fourth (n = 4) doses the bleeding time lengthened by a mean of 60 s (95% CI 37 to 83; P Sheffield 2011 [22] (20 very low birth weight neonates, 23 to 30 weeks, first week of life; abstract via a PubMed summarizer): baseline bleeding time 166 s (95% CI 138 to 194); after a short course of 4 to 7 doses (n = 10) values returned to about baseline; with 10 to 15 doses (n = 10) bleeding time rose to 284 s (95% CI 242 to 326; P = 0.001 versus the initial value); dose count correlated with the prolongation (r = 0.68); PFA-100 time trended longer, not significant (P = 0.07). All blood cultures were sterile. Fass 1987 [23] studied ticarcillin, piperacillin and mezlocillin with cefotaxime as control in 156 adults; ampicillin was not among the drugs, so that platelet-bleeding result is class information only and is not used for ampicillin. The NIH vitamin K fact sheet [24] says antibiotics "can destroy vitamin K-producing bacteria in the gut, potentially decreasing vitamin K status", names only cefoperazone, and does not mention ampicillin or penicillins.

Mechanism

For the bleeding outcome: platelet dysfunction is the route the cited authors point to (bleeding time and PFA-100 platelet function testing [21][22]). For vitamin K: reduced vitamin K-producing gut bacteria is a proposal in a reference fact sheet, not demonstrated for ampicillin. CLASS EXTRAPOLATION applies to the vitamin K route: ampicillin was not in the cohort of any vitamin K-measuring study located (none were located at all).

Counter-evidence held on record

Counter-evidence and confounding Both neonatal studies are small, single-center, pre/post designs without an unexposed arm; bleeding time normally shortens during the first week of life in very low birth weight infants, which the authors note makes the prolongation more striking [22], but sepsis, prematurity and other drugs cannot be excluded. No clinical bleeding outcome is reported in the abstracts read. Framing caution A hematologic monitoring prompt, not a vitamin K deficiency claim. Do not infer that vitamin K should be added. Decisions about prophylaxis in neonates belong to the neonatal team.

Vitamin B12 and folate: ampicillin inhibited the Lactobacillus leichmannii B12 microbiological assay (falsely low readings); the folate assay was unaffected; no status data

Yellow — Low

See study details

In a 1969 hospital series, serum B12 microbiological assays were inhibited in samples from patients on ampicillin while the radioisotope and Euglena methods were not, which is a laboratory artifact rather than evidence of lowered B12 in the body.

Full detail and limits

Limits on what this shows

Null findings: The folate assay null above [31]. Asbjornsen 1974 (effect of serum antibiotic concentrations on the L. casei folate assay) is indexed with ampicillin as a MeSH term but its abstract was not available, so its result is not used [31].
At-risk subgroups: Anyone whose B12 is measured by a microbiological assay while on ampicillin. Whether current routine B12 methods are affected was not examined in the sources read.

Direction

MEASUREMENT ARTIFACT (falsely low reading in one assay method). Not a depletion and not evidence that B12 or folate status fell (Hard Rules 2 and 3).

Regulatory status

Neither B12 nor folate is mentioned in the label text read. The labels do record a separate laboratory interference: copper-reduction urine glucose tests can read falsely positive with high urine ampicillin [1][2][3].

Population evidence

Powell 1969 [30] (Tier A for the assay finding; J Clin Pathol; abstract read as an OpenAlex reconstruction): of 750 consecutive serum vitamin B12 assays by L. leichmannii, 25 (3.3%) showed inhibition; a drug history was available in 23 and 17 of these were receiving ampicillin; two others were on phenoxymethylpenicillin or phenethicillin; in a prospective study of 11 patients, inhibition appeared in 7 during ampicillin therapy at varying intervals. B12 measured by the radioisotope and Euglena gracilis methods was not affected; inhibition was reproduced in vitro at ampicillin concentrations corresponding to therapy, whereas benzylpenicillin, streptomycin and chloramphenicol had no such effect. The authors state that other methods may be needed to distinguish the inhibition from true B12 depletion. Shojania and Hornady 1969 [31] (Am J Clin Pathol; abstract via an OpenAlex reconstruction; adults sampled before and 2 hours after a 24-hour antibiotic test dose): sulfisoxazole, erythromycin, lincomycin and novobiocin gave falsely low folate readings in the Lactobacillus casei assay, whereas penicillin, ampicillin, chloramphenicol, colistimethate, streptomycin, tetracycline, kanamycin and nitrofurantoin had no inhibitory effect.

Mechanism

Ampicillin inhibits growth of the assay organism (L. leichmannii) in vitro [30]. No mechanism for any change in body B12 or folate status.

Cohort test

Powell included ampicillin as the dominant drug; Shojania included ampicillin by name. Both are laboratory-method studies, not nutrient-status cohorts.

Counter-evidence held on record

Counter-evidence and confounding The series is historic (1969) and the assay method is largely superseded; the study cannot show that body B12 stores were unchanged, only that other methods were not affected in the same samples. The authors note inhibition also occurred in people with no known drug intake. Framing caution A low B12 reading taken during ampicillin therapy should be confirmed by a different method before being read as a deficiency. This entry is not a reason to take B12 or folate.

Food and oral absorption: a meal lowered oral ampicillin exposure by about 31% in a crossover study (food affecting the drug; timing interaction, not depletion)

Yellow — Low

See study details

In 16 healthy subjects, a non-fasting 500 mg ampicillin dose gave a lower peak and AUC than a fasting dose, so the capsule label tells patients to take it at least half an hour before or two hours after meals.

Full detail and limits

Limits on what this shows

Null findings: None for ampicillin. Amoxicillin showed little food effect in the same crossover [8], which is a reason not to carry this finding across aminopenicillins.

Direction

Nutrient or food AFFECTING THE DRUG, not the drug depleting a nutrient. Filed as a timing interaction with a separation interval (Hard Rule 4). Yellow at most.

Regulatory status

Capsule label: the drug "should be administered at least one-half hour before or two hours after meals for maximal absorption"; the patient information gives the same timing [3]. The injection labels read carry no food statement [1][2].

Population evidence

Eshelman and Spyker 1978 [8] (Tier A, double-blind crossover, 16 normal subjects, single 500 mg oral dose fasting and non-fasting; abstract via an OpenAlex reconstruction): peak serum level 5.4 mcg/mL fasting versus 4.0 non-fasting, AUC 17.4 versus 12.0 h x mcg/mL (about 31% lower), urinary recovery 37% versus 29%; the authors concluded that ampicillin is better absorbed fasting. In the same study amoxicillin absorption was little affected by food (AUC 26.9 versus 22.2; urinary recovery 47% versus 44%). A pharmacology reference record quotes: "intake of food prior to ingestion of ampicillin results in less complete absorption" [6]. P values and confidence intervals are not in the abstract read.

Mechanism

Reduced absorption in the fed state; the specific cause (gastric emptying, binding to food, other) was not retrieved.

Counter-evidence held on record

Counter-evidence and confounding Single-dose study in healthy volunteers (1978) with a one-compartment model; clinical effect of a 31% lower exposure on cure was not examined. Probenecid, renal function and the dosage form change exposure independently. Framing caution A dosing-time instruction from the label, not a nutrient finding. No supplement separation interval is given by the label read and none is recommended here.

The five body-system areas

Each finding is counted once, in a single area. Where a study is mentioned in a second area it is context only.

Mitochondrial Burden

Each finding below is counted once, in this area only.

Mitochondrial burden: no ampicillin-specific mitochondrial measurement; a null apoptosis result in human neurons, a combination result with ibuprofen in endothelial cells, and piperacillin class extrapolation

Yellow — Low

See study details

In vitro, ampicillin did not induce apoptosis in human primary neurons and neuron lines (while four other antibiotics did, three with mitochondrial dysfunction), ampicillin plus ibuprofen showed mitochondrial fission and ROS in endothelial cells, and the reduced-respiration finding belongs to piperacillin; no human mitochondrial measurement exists.

Full detail and limits

Limits on what this shows

Null findings: Xiao 2019 as above [32]. No ampicillin respirometry study was located.

Direction

Unclear to neutral for ampicillin alone; possible excess burden with ibuprofen combination in vitro. A drug toxicity question, not a nutrient deficiency.

Regulatory status

Mitochondrial effects are not mentioned in the label text read [1][2][3].

Population evidence

None in humans. Xiao 2019 [32] (Tier B, ampicillin by name; human primary neurons and neuron cell lines; abstract via an OpenAlex reconstruction and a PubMed summarizer): metronidazole, tigecycline, azithromycin and clindamycin induced apoptosis at clinically relevant concentrations, "but not ampicillin or sulfamethoxazole"; mitochondrial dysfunction, loss of membrane potential and an energy crisis were reported for tigecycline, azithromycin and clindamycin, and the abstract says nothing else about ampicillin; concentrations are not in the abstract. Zhao 2025 [33] (Tier B, ampicillin by name, combined with ibuprofen; HUVEC): antibiotic plus ibuprofen combinations (kanamycin, azithromycin, ampicillin or ciprofloxacin) triggered mitochondrial fission, ROS overproduction and mitofusin 2 down-regulation; ampicillin-specific results are not separated in the abstract and ibuprofen is a confounder. Jiang 2018 [35] (CLASS EXTRAPOLATION): piperacillin, not ampicillin, reduced respiration, membrane potential and ATP production in SH-SY5Y cells and human primary neurons. Kalghatgi 2013 [34]: the abstract reports mitochondrial dysfunction and ROS with quinolones, aminoglycosides and beta-lactams in mammalian cells and mice but does not name the beta-lactam; full text could not be opened (PMC bot check, Science page error), so no ampicillin result is borrowed.

Mechanism

Not shown for ampicillin. For piperacillin the authors attribute neuronal death to mitochondrial dysfunction and oxidative damage, reversed by N-acetylcysteine [35].

Cohort test

CLASS EXTRAPOLATION for Jiang 2018 (a ureidopenicillin; ampicillin NOT in the cohort); Kalghatgi 2013 not usable (ampicillin not confirmed in the cohort). Zhao 2025 includes ampicillin only with ibuprofen. Capped at yellow; no human source, so orange is unavailable.

Counter-evidence held on record

Counter-evidence and confounding Concentrations and cell types differ between studies, the positive findings are combination or other-drug findings, and the only ampicillin-alone result is an apoptosis null reported at abstract level. Framing caution Theoretical, in vitro. Do not present ampicillin as mitochondrially toxic in people, and do not recommend mitochondrial or antioxidant supplements from this entry.

Oxidative Stress

Each finding below is counted once, in this area only.

Oxidative stress: no ampicillin-specific marker data in animals or people; ROS appeared in an ampicillin plus ibuprofen combination in vitro and with piperacillin (class extrapolation)

Yellow — Low

See study details

No study measured glutathione, malondialdehyde or antioxidant enzymes in ampicillin-exposed people or animals; the available signals are an in vitro combination with ibuprofen and a piperacillin neuron study.

Full detail and limits

Limits on what this shows

Null findings: Xiao 2019 as above [32]. No human null for oxidative markers was found.

Direction

Possible excess oxidative burden in vitro. No antioxidant nutrient was measured, so this is not a nutrient depletion.

Regulatory status

Not mentioned in the label text read [1][2][3].

Population evidence

None in humans. The PubMed listing "ampicillin oxidative stress glutathione malondialdehyde" returned wheat, mouse, rabbit, rat, dog and bacterial studies and two human Helicobacter pylori regimens that included amoxicillin; none measured oxidative markers after ampicillin in animals or people [37]. Zhao 2025 [33]: ROS overproduction with antibiotic plus ibuprofen combinations including ampicillin (HUVEC; ampicillin alone not separated). Xiao 2019 [32]: oxidative damage reported for tigecycline, azithromycin and clindamycin; ampicillin did not induce apoptosis and the abstract reports no ampicillin ROS finding. Jiang 2018 [35] (piperacillin, not ampicillin): increased mitochondrial superoxide and ROS and oxidative DNA, protein and lipid damage in neurons, abolished by N-acetylcysteine.

Mechanism

Not shown for ampicillin.

Cohort test

CLASS EXTRAPOLATION for Jiang 2018 (piperacillin, a different penicillin; ampicillin not in the cohort). Kalghatgi 2013 not usable (ampicillin not confirmed) [34]. Capped at yellow.

Counter-evidence held on record

Counter-evidence and confounding Infection and inflammation raise oxidative markers in patients regardless of the drug; the in vitro combination result includes ibuprofen. Framing caution Theoretical signal only. Do not present as an expected effect in people and do not recommend antioxidant supplements.

Copper and Iron Balance

Copper and iron are assessed separately. Nothing here is counted twice.

Copper: in vitro degradation or reduced activity of ampicillin in the presence of copper ions (copper acting on the drug); no human copper measurement

Yellow — Low

See study details

A 2023 review of in vitro studies states that ampicillin is degraded or less active in the presence of copper ions, but no study measured copper status in people given ampicillin.

Full detail and limits

Limits on what this shows

Null findings: No human study of ampicillin with a copper outcome was found.

Direction

Nutrient (metal) AFFECTING THE DRUG in vitro, not the drug depleting copper (Hard Rule 4).

Regulatory status

Copper is not mentioned in the label text read [1][2][3].

Population evidence

None in humans. Bozic Cvijan 2023 [36] (review of in vitro studies; abstract via an OpenAlex reconstruction): "In vitro-described degradation or lower antimicrobial activity of amoxicillin, ampicillin, cefaclor, ceftriaxone, and meropenem in the presence of Cu ions suggest caution when using prescribed antibiotics in patients with altered Cu levels"; no concentrations are in the abstract. The primary study (Bozic 2018, Free Radic Biol Med) lists ampicillin among its indexing terms but its abstract was not available [36]. The PubMed listing "ampicillin copper complex" returned 34 results; the first 10 were reviews, chemistry and in vitro studies, none human [37].

Mechanism

Coordination and metal-catalysed hydrolysis chemistry in vitro. Physiological relevance (plasma copper, absorption, excretion) is not shown.

Counter-evidence held on record

Counter-evidence and confounding The primary in vitro studies were not opened. Copper status was not measured in anyone. Framing caution Not a depletion claim and not a reason to take copper; no copper dose is recommended and no dose appears in this dossier.

Iron

Not graded — disclosed evidence gap

See study details

No evidence was found that ampicillin alters iron absorption, status or loss, and no circulating claim about iron and ampicillin was found.

Full detail and limits

What the grade means here: Nothing has been measured here, so this finding cannot be graded. That does not establish either safety or harm, and it is not the same as a White result. Ungraded

Limits on what this shows

Why no grade: Dual condition met: no Tier B or C source was found to support even a yellow grade, and no circulating consumer claim linking iron and ampicillin was found to rebut. Hemolytic anemia is a separate outcome entry (Oxygen delivery/utilization), not an iron finding. This is a disclosed gap, not a finding of safety; re-check with full label text and PubMed access.

What was searched

Label extractions (injection labels [1][2], capsule label [3]): the extraction prompts did not target iron by name, and no iron or other mineral interaction was returned in any of the items extracted (this is a limit: the full labels were not searched for the word iron). PubMed listing "ampicillin iron absorption OR ferritin OR serum iron": the Boolean query did not parse and returned unrelated ferritin and iron papers (ten records, none involving ampicillin) [37]. PubMed listing "ampicillin ferrous sulfate absorption": one record, a Helicobacter pylori eradication trial in iron-deficiency anemia that used an amoxicillin-containing regimen with oral iron, which is amoxicillin as treatment and not an ampicillin-iron study [37]. PubMed listing "ampicillin copper complex" (34 results, metal chemistry and in vitro work, no iron outcome in people) [37]. Hemolysis literature was searched separately (see Oxygen delivery/utilization) and is not an iron finding.

Channel outcomes

The open-web search budget was exhausted before consumer-claim and iron-specific web searches could be run; the Antidote Research ampicillin page returned a fetch error and Drugs.com interaction pages were not tried. PubMed listings were spaced because of repeated 429 responses. Result is mixed: no relevant record on the channels that worked, plus tooling limits on others. A thin literature is likely but not established.

Gut Microbiome Risk

Each finding below is counted once, in this area only.

Gut microbiome risk: lower Bifidobacterium and higher Enterobacteriaceae/Proteobacteria in infants after ampicillin (alone via maternal prophylaxis, or with gentamicin), partly recovered within 4 to 8 weeks; community C. difficile association; bounded to perinatal and neonatal exposure

Orange — Moderate

See study details

In infants, ampicillin exposure was followed by more Enterobacteriaceae or Proteobacteria and fewer bifidobacteria, with bifidobacteria largely recovered by day 30 to 8 weeks but Proteobacteria and Enterobacteriaceae still higher in some groups; in adults, ampicillin exposure is associated with community-onset C. difficile infection (adjusted OR 2.6).

Full detail, limits and 1 references

What the grade means here: At least one Tier A source with this drug in the cohort showing a real but bounded deficit: an exposure window, a subgroup, low frequency, or a functional rather than circulating deficit. Orange

Limits on what this shows

Null and limiting findings: Chang 2021 [11]: 24 very-low-birth-weight infants analyzed (10 given ampicillin plus gentamicin for 3 days, 14 given ampicillin plus cefotaxime for 7 days), sampled on days 7, 14 and 30. Shannon diversity did not differ between regimens; beta diversity at day 7 was not significant (P = 0.131); Bifidobacterium did not change significantly in either group; Enterococcus was higher with the cefotaxime regimen (P = 0.002). There was no unexposed group, so this does not test ampicillin against no antibiotic. The authors list no unexposed control, no birth stool samples, different durations and small size as limits. No Tier A study of ampicillin that found no microbiome change was located. In Imoto the differences disappeared by 6 months [13]; in Mazzola bifidobacteria recovered by day 30 [12].
At-risk subgroups: Preterm and breastfed infants (largest shifts in the cohorts above); people with other C. difficile risk factors (not assessed here); longer courses (5 to 7 days versus fewer in Greenwood).

Direction

Disturbance of the gut microbial community and an infection-risk association (a risk entry). It is not a nutrient deficiency and implies no supplementation.

Regulatory status

Injection label: "Treatment with antibacterial agents alters the normal flora of the colon leading to overgrowth of C. difficile"; CDAD "has been reported to occur over two months after the administration of antibacterial agents"; enterocolitis, pseudomembranous colitis and diarrhea are listed reactions [1][2][3]. Capsule label carries the same CDAD and colon-flora text [3].

Population evidence

Mazzola 2016 [12] (Tier A, ampicillin alone but indirect: mothers received intrapartum ampicillin against group B Streptococcus; infant stool at days 7 and 30; 16S V3-V4 and qPCR). Breastfed antibiotic-exposed infants had Enterobacteriaceae at 52% versus 14% in controls (p = 0.044; versus 16% in mixed-fed, p = 0.13, not significant) and lower diversity at day 7; Bifidobacteria were reduced in breastfed (p = 0.001) and mixed-fed exposed groups, recovered by day 30 (breastfed p = 0.025, mixed-fed p = 0.013), while Enterobacteriaceae stayed highest in exposed breastfed infants (44% versus 16% in controls and 28% in exposed mixed-fed). Group sizes and ampicillin dosing were not retrievable (abstract only). Aloisio 2014 [14], from the same group on the same prophylaxis question, could not be read (no abstract in the record opened) and is not counted as independent. Fouhy 2012 [9] (Tier A, ampicillin plus gentamicin, parenteral within 48 hours of birth; 9 treated infants versus 9 controls; sampled 4 and 8 weeks after treatment). At 4 weeks Proteobacteria were higher (P = 0.0049), Actinobacteria lower (P = 0.00001), Bifidobacterium lower (P = 0.0132) and Lactobacillus lower (P = 0.0182); at 8 weeks Proteobacteria were still higher (P = 0.0049) while Actinobacteria, Bifidobacterium and Lactobacillus had recovered, though total Bifidobacterium counts and species number stayed reduced. Greenwood 2014 [10] (Tier A, ampicillin plus gentamicin; 74 infants born at 32 weeks or less, grouped by 0, 1 to 4 or 5 to 7 days of empiric ampicillin and gentamicin in week 1). The 5 to 7 day group had higher relative Enterobacter (P =.016) and lower diversity in weeks 2 and 3; early antibiotics were also associated with more necrotizing enterocolitis, sepsis or death than in unexposed infants (an association with confounding by illness, not a nutrient finding). The abstract gives no confidence intervals. Imoto 2021 [13] (Tier A for a mixed exposure): 130 Japanese infants whose mothers received cefazolin (before cesarean) or ampicillin (premature rupture of membranes or group B Streptococcus positive); low Bifidobacterium at 1 and 3 months in exposed infants; all differences gone by 6 months. Ampicillin was not analyzed separately in the abstract. Miller 2023 [15] (Tier A, ampicillin in the cohort by name, outpatient claims): 159,404 community-associated C. difficile cases and 797,020 matched controls; ampicillin within 30 days before index, 178 cases and 220 controls exposed, unadjusted OR 4.05, adjusted OR 2.6 (95% CI 2.00 to 3.39), adjusted for other antibiotics, comorbidities, proton-pump inhibitors and health-care visits; for comparison amoxicillin 1.96 (1.88 to 2.04), penicillin 1.80 (1.59 to 2.03), amoxicillin-clavulanate 8.53 (8.23 to 8.85). Read through a summarizing fetch tool of the journal page. Animal (Tier B, ampicillin itself): in mice, 14 days of therapeutic-dose ampicillin lowered alpha diversity, enriched Enterococcus and Klebsiella, depleted Lachnospiraceae, raised succinate, lowered butyrate and halved colonic ZO-1 and occludin [18]; one week of ampicillin reduced diversity in another mouse study [19]; perinatal ampicillin in dams reduced Muribaculaceae and altered bile acids, with increased offspring weight gain [20] (abstracts only).

Mechanism

Named: antibacterial activity against susceptible commensal bacteria (label flora statement [1][3]) with delivery of active drug to the gut by biliary excretion and enterohepatic circulation [6][1], and overgrowth of resistant organisms (Enterobacteriaceae in the infant cohorts).

Cohort test

Neonatal ampicillin plus gentamicin [9][10]: ampicillin IS in the cohort as one component of a two-drug regimen; gentamicin cannot be separated (the gentamicin dossier in this batch graded the same sources orange for that reason). Chang [11]: ampicillin in both arms; active-comparator only. Mazzola [12]: ampicillin alone, but delivered to the infant indirectly. Miller [15]: ampicillin named and analyzed alone. Baxter 2008 [16] (case-control of 1,142 hospital-acquired CDAD cases): ampicillin is not named in the abstract and the full text could not be opened, so the cohort test is not passed and no result is borrowed. Liu 2024 [17] (61 randomized trials plus an adverse-event database): ampicillin is not named in the abstract, so no result is borrowed. A "Zhang 2022" C. difficile cohort named in the assignment could not be identified by author, year and topic searches; nothing is cited for it.

Why orange, not red

Red hunt applied (see the Red tier above). At least one Tier A source with ampicillin in the cohort shows a real effect, but it is bounded to infants and neonates, partly transient, not separable from gentamicin in two of three infant cohorts, and the adult evidence is a claims-based C. difficile outcome rather than a microbiome measurement.

Counter-evidence held on record

Counter-evidence and confounding Infection or prematurity itself, feeding type, delivery mode and co-administered drugs confound the infant cohorts; Fouhy is small (9 versus 9); Mazzola is an abstract-level read with no group sizes; the Miller odds ratio comes from claims data with an exposure window of 30 days and indication confounding is likely (people prescribed ampicillin are being treated for infections). Bifidobacteria recovered in the cohorts that followed them to a later time point (Mazzola, Fouhy, Imoto). Framing caution This is a disturbance and infection-risk entry, not a deficiency. No probiotic, fiber or vitamin supplement is recommended by this entry. New severe or persistent diarrhea during or after a course, which the label says can occur more than two months later, needs clinical assessment for C. difficile.

Imoto N, Kano C, Aoyagi Y, et al. Administration of beta-lactam antibiotics and delivery method correlate with intestinal abundances of Bifidobacteria and Bacteroides in early infancy, in Japan. Sci Rep 2021. — Tier A for a mixed exposure (130 infants; cefazolin before cesarean, ampicillin for premature rupture of membranes or group B Streptococcus; 383 stool samples). PMID 33737648, DOI 10.1038/s41598-021-85670-z. Abstract read as an OpenAlex reconstruction; ampicillin not analyzed separately in the abstract.Mixed exposure; abstract only.

Oxygen and ATP Output

Oxygen delivery and ATP production are assessed separately. Nothing here is counted twice.

Oxygen delivery/utilization: label-listed anemia and a single 1974 case-report record of hemolytic anemia (adverse outcome, not a nutrient deficiency)

Yellow — Low

See study details

The ampicillin labels list anemia, thrombocytopenia and related blood reactions as usually reversible hypersensitivity phenomena, and one indexed case report describes ampicillin-induced hemolytic anemia in a child, but no incidence or hemoglobin cohort exists.

Full detail and limits

Limits on what this shows

Null findings: None located; the absence of a cohort is an evidence gap, not reassurance.
At-risk subgroups: Not defined for ampicillin from the sources read.

Direction

Drug toxicity (hypersensitivity-type blood reactions). Not iron deficiency and not an oxygen-carrying nutrient deficit (Hard Rule 2). Kept separate from the Iron and ATP entries (Hard Rule 7).

Regulatory status

Labels: "Anemia, thrombocytopenia, thrombocytopenic purpura, eosinophilia, leukopenia, and agranulocytosis have been reported", usually reversible on discontinuation and believed to be hypersensitivity phenomena [1][2][3]. Hemolytic anemia is NOT named in the label text read and the Coombs (direct antiglobulin) test is not mentioned [1][2][3].

Population evidence

Thomson and Williamson 1974 [28] (Tier B case report; PubMed record only): "A case of ampicillin-induced haemolytic anemia" in a preschool-age boy treated for otitis media or a respiratory tract infection per the indexing; the record has no abstract, so the antiglobulin result, hemoglobin and outcome are not known. Two reviews of drug-induced immune hemolytic anemia [29] (Garratty 2012 and Garratty and Arndt 2014) do not name ampicillin in their abstracts and identify piperacillin, cefotetan and ceftriaxone as the commonest causes. No hemoglobin or hematocrit comparison of ampicillin users with non-users was located.

Mechanism

Immune red-cell destruction is the general mechanism of the class in the reviews [29]; it was not tested for ampicillin in any source read.

Counter-evidence held on record

Counter-evidence and confounding The case record is an indexing entry only. The reviews found do not list ampicillin among commonly implicated drugs, and the label does not name hemolytic anemia. Framing caution Jaundice, dark urine, new pallor or unexplained fatigue during a course should be reported to a clinician. This entry is not an iron or oxygen-delivery deficiency and supports no iron supplement.

ATP production: no ampicillin ATP measurement; reduced ATP production reported for piperacillin in human neurons (CLASS EXTRAPOLATION); ampicillin did not produce the apoptosis seen with the energy-crisis drugs

Yellow — Low

See study details

No study measured cellular ATP after ampicillin; the lowered ATP production in human neurons belongs to piperacillin, and in a six-antibiotic neuron screen the energy-crisis findings were reported for other drugs while ampicillin did not induce apoptosis.

Full detail and limits

Limits on what this shows

Null findings: Xiao 2019 as above [32].

Direction

Drug-toxicity direction for piperacillin in vitro; unknown for ampicillin. Not a nutrient deficiency.

Regulatory status

Not mentioned in the label text read [1][2][3].

Population evidence

None in humans. Jiang 2018 [35]: piperacillin at clinically relevant doses reduced respiration, membrane potential and ATP production in SH-SY5Y cells and human primary neurons (concentrations and magnitudes not retrievable from the abstract record). Xiao 2019 [32]: "an energy crisis" is described for tigecycline, azithromycin and clindamycin; ampicillin is reported only as not inducing apoptosis. The PubMed listing "ampicillin ATP mammalian cells mitochondria" returned two records, a bacterial protein-expression paper and the piperacillin study [37].

Mechanism

Not shown for ampicillin.

Cohort test

CLASS EXTRAPOLATION: ampicillin was NOT in the Jiang cohort. Capped at yellow.

Counter-evidence held on record

Counter-evidence and confounding A different penicillin, different cell lines and no ampicillin ATP endpoint. The shared origin with the mitochondrial and oxidative entries is recorded in the Overlap map. Framing caution No energy-depletion claim is supported for people. Do not recommend ATP-support or mitochondrial supplements from this entry.

Claims checked and not supported

These circulate online for this medication. They are listed here only so they can be answered, never as findings, and they are not graded.

A claim with no supporting evidence is not necessarily disproven. Where evidence actually argues against a claim, that is stated below.

B vitamins (B12, folate, biotin) lost through reduced gut-flora synthesis (provisional, tooling-limited)
Where it comes from: General consumer and supplement-retail framing that antibiotics deplete B vitamins. No page asserting this for ampicillin was found: the Antidote Research ampicillin page returned a fetch error and the web-search budget was exhausted, so the claim is not traced to a specific origin.
Why it fails: No ampicillin study measured B12, folate or biotin status. The only ampicillin B12 finding is a falsely low microbiological assay reading with other methods unaffected, and ampicillin did not inhibit the folate assay [30][31]; neither supports depletion. Held out of publication as a deficiency claim pending a re-check that could convert it to yellow.
"Antibiotics cause vitamin K deficiency, so ampicillin causes bleeding through vitamin K" (stated as fact)
Where it comes from: Reference fact-sheet statement about antibiotics in general [24] and the general idea that gut-bacteria loss lowers vitamin K.
Why it fails: The NIH fact sheet uses hedged wording ("potentially"), names cefoperazone only, and does not mention ampicillin or penicillins [24]. The ampicillin bleeding data are bleeding-time prolongations in neonates, a platelet-function measure, with no vitamin K measurement [21][22]. Carried as yellow with this limit stated, not as an established deficiency.
Ampicillin "wipes out" or permanently destroys gut flora
Where it comes from: Generic consumer and probiotic-marketing framing; not traced to a single page.
Why it fails: Where infants were followed, bifidobacteria recovered by day 30 [12] or 8 weeks [9] and differences were gone by 6 months in another cohort [13]. "Permanent" fails as stated. It is not a reassurance either: Proteobacteria were still higher at 8 weeks [9], Enterobacteriaceae remained at 44% versus 16% at day 30 in exposed breastfed infants [12], and C. difficile risk was raised in the community case-control (adjusted OR 2.6) [15].
Ampicillin damages mitochondria, causes oxidative stress or lowers cellular energy in people
Where it comes from: The bactericidal-antibiotic mitochondrial toxicity literature (Kalghatgi 2013, beta-lactam not named in the abstract read [34]) and other-antibiotic neuron studies [32][35].
Why it fails: No human measurement of mitochondrial function, oxidative markers or ATP exists for ampicillin. In the one neuron screen that named it, ampicillin did not induce apoptosis while other antibiotics did [32]; the positive findings are for piperacillin [35] or ampicillin combined with ibuprofen in vitro [33]. Stated as a human effect it fails; the signals are carried as yellow entries with these limits.

How the body handles this medication

Metabolism and enzymes: About 20% of a 250 to 500 mg dose is metabolized in healthy subjects (5R,6R- and 5S,6R-penicilloic acid; piperazine-2,5-dione after oral intake); within 12 hours about 7% of the dose appears in urine as metabolites. The human enzymes are not named; the only enzyme named is bacterial penicillinase. No CYP450 inhibition or induction is stated in the label text read.[5] HSDB via PubChem (IARC, Goodman and Gilman); [1][2][3] labels
Elimination: "Ampicillin is excreted largely unchanged in the urine"; probenecid inhibits renal tubular secretion and delays excretion. In infants under 28 days the half-life shortens as postmenstrual age increases. An adult half-life is not in the label text read (a general reference gives about 1 hour; Tier D).[1][3] labels; [7] Wikipedia
Absorption and food: Oral absorption is 30 to 55% in fasting adults, with peak serum levels about 2 hours after the dose. The capsule label says to give it "at least one-half hour before or two hours after meals for maximal absorption". In a 16-subject crossover, a 500 mg dose gave an AUC of 17.4 fasting versus 12.0 non-fasting (about 31% lower). No absorption transporter is named in the sources read.[3] label; [6] HSDB; [8] Eshelman 1978
Biliary excretion and gut exposure: The drug appears in bile, undergoes enterohepatic circulation and is excreted in feces; biliary concentration depends on the integrity of the gallbladder and ducts. The injection label states the active form reaches higher concentrations in bile than in serum.[6] HSDB; [1] label
Electrolyte content: Ampicillin for injection contains 2.9 mEq (65.8 to 66 mg) of sodium per gram. The WHO defined daily dose for parenteral use is 6 g, which by simple multiplication carries about 17 mEq (about 396 mg) of sodium. The labels read make no statement on potassium or hypokalemia.[1][2] labels; [4] ATC/DDD (arithmetic is the reviewer's)
Interactions of nutritional interest: Allopurinol "increases substantially the incidence of skin rashes" (a drug-drug effect, not a nutrient finding). Oral contraceptives "may be less effective" (capsule label). Copper-sulfate urine glucose tests can read falsely positive; enzyme-based tests are not affected. The capsule label notes a transient fall in plasma conjugated estriol in pregnant women. No mineral, antacid or vitamin interaction was returned from the label extractions.[1][2][3] labels

What the research says is worth watching

General information from the medication label and the studies above. It is not personal medical advice, and any change belongs with your prescriber.

Symptoms / during and after a course
Severe or persistent diarrhea
New watery or bloody diarrhea during or after a course, with cramping or fever, warrants clinical assessment for C. difficile infection; the label says it can occur more than two months after antibacterial treatment [1][3]. This is a clinical outcome, not a nutrient finding.
Electrolytes / high-dose or prolonged IV therapy
Sodium and potassium
Serum sodium and potassium are reasonable to follow in hospitalized patients on repeated IV doses, particularly with heart failure, kidney disease or large burns, because the injection carries 2.9 mEq of sodium per gram [1][2] and potassium fell by about 0.28 mEq/L in a matched ampicillin-sulbactam cohort [25]. The labels make no potassium statement. Excess/retention and disturbance signals: the response is a prescriber decision, not a supplement.
Hematology / neonates and prolonged IV courses
Bleeding time, platelets and blood count
In neonates, bleeding time lengthened after about 3 to 4 doses in late-preterm and term infants and after 10 or more doses in very low birth weight infants [21][22]; new bruising, bleeding or pallor in any patient warrants a platelet count and blood count (anemia and thrombocytopenia are label-listed [1][2][3]). Vitamin K is not the indicated remedy from these data; decisions belong to the clinical team.
Laboratory method
B12 and urine glucose tests
If a serum B12 is low during ampicillin therapy, confirm it by a non-microbiological method before calling it a deficiency: in 1969 the L. leichmannii assay was inhibited while radioisotope and Euglena methods were not [30]. Whether current automated methods are affected was not examined. Copper-reduction urine glucose tests (Clinitest, Benedict, Fehling) can read falsely positive at high urine ampicillin; enzyme-based tests are not affected [1][2][3].
Timing / oral dosing
Meals and capsules
The capsule label says to take ampicillin at least half an hour before or two hours after meals for maximal absorption [3]; a crossover study found about 31% lower AUC after a meal [8]. No vitamin, mineral or antacid separation interval is given in the label text read. No supplement dose is recommended or appears in this dossier.
Drug interactions (not nutrient findings)
Allopurinol, probenecid, oral contraceptives
Allopurinol with ampicillin substantially increases the incidence of skin rashes [1][3]; probenecid delays ampicillin excretion and the capsule label warns of increased blood levels [3]; the capsule label states oral contraceptives "may be less effective" [3].
Special populations
Neonates, pregnancy, kidney function
Neonatal dosing follows gestational and postnatal age and the half-life shortens as postmenstrual age increases; bacteriostatic water is not to be used as a diluent in newborns [1]. The capsule label notes a transient fall in plasma conjugated estriol in pregnant women [3]. Ampicillin is largely excreted unchanged by the kidney [1][3]; renal dose adjustment text was not retrieved from the label extractions.

Overlap map, to prevent double counting

Gut microbiome risk
Shares evidence with: Vitamin K and bleeding; Fails verification: B vitamins and "wiped-out flora"
Note: The same mechanism (loss of susceptible gut bacteria, label colon-flora statement) underlies the proposed vitamin K route and the B-vitamin claim. Treat as one mechanism, not three confirmations. The neonatal ampicillin plus gentamicin sources [9][10] are also the sources of the gentamicin dossier's microbiome entry in this batch and are one body of evidence.
Mitochondrial burden
Shares evidence with: Oxidative stress; ATP production
Note: Same sources: Xiao 2019 [32], Zhao 2025 [33], Jiang 2018 (piperacillin) [35] and the unusable Kalghatgi 2013 abstract [34]. Oxidative stress and ATP production add no independent evidence beyond these studies.
Sodium
Shares evidence with: Potassium
Note: Bamberg [27], Tashiro [25] and Ryu [26] are all hospitalized-adult cohorts of ampicillin-sulbactam and/or piperacillin-tazobactam, and the labels [1][2] supply the sodium figure. They address different nutrients, but the exposure and population overlap, so the two entries cannot be added together.
Oxygen delivery/utilization
Shares evidence with: Vitamin K and bleeding; Iron (ungraded)
Note: The same label sentence lists anemia and thrombocytopenia [1][2][3]. Hemolytic anemia is a drug-toxicity outcome and not an iron finding; Iron has no evidence of its own.
Copper
Shares evidence with: Iron; Food and oral absorption
Note: No shared source with Iron. Copper and Food are both nutrient-to-drug interactions (Hard Rule 4) but rest on different studies [36][8].
Vitamin B12 and folate
Shares evidence with: Fails verification: B vitamins
Note: Powell [30] and Shojania [31] are the only B-vitamin sources and are laboratory-assay findings; they are cited in both places and are not independent evidence of depletion.

All references used above

Ampicillin

Findings for this medication

What the research found

Sodium: label sodium load of ampicillin sodium (excess/retention direction); a pooled burn-unit cohort shows a small serum sodium rise; ampicillin not separable

Potassium: serum potassium fell by a mean of 0.28 mEq/L with ampicillin-sulbactam in a matched hospital cohort; combination and active-comparator design; disturbance, not dietary depletion

Vitamin K and bleeding: bleeding time lengthened in two neonatal ampicillin cohorts (a platelet-function outcome); vitamin K never measured; no ampicillin INR signal on the labels read

Vitamin B12 and folate: ampicillin inhibited the Lactobacillus leichmannii B12 microbiological assay (falsely low readings); the folate assay was unaffected; no status data

Food and oral absorption: a meal lowered oral ampicillin exposure by about 31% in a crossover study (food affecting the drug; timing interaction, not depletion)

The five body-system areas

⚡Mitochondrial Burden

Mitochondrial burden: no ampicillin-specific mitochondrial measurement; a null apoptosis result in human neurons, a combination result with ibuprofen in endothelial cells, and piperacillin class extrapolation

💥Oxidative Stress

Oxidative stress: no ampicillin-specific marker data in animals or people; ROS appeared in an ampicillin plus ibuprofen combination in vitro and with piperacillin (class extrapolation)

⚖️Copper and Iron Balance

Copper: in vitro degradation or reduced activity of ampicillin in the presence of copper ions (copper acting on the drug); no human copper measurement

Iron

🌿Gut Microbiome Risk

Gut microbiome risk: lower Bifidobacterium and higher Enterobacteriaceae/Proteobacteria in infants after ampicillin (alone via maternal prophylaxis, or with gentamicin), partly recovered within 4 to 8 weeks; community C. difficile association; bounded to perinatal and neonatal exposure

💨Oxygen and ATP Output

Oxygen delivery/utilization: label-listed anemia and a single 1974 case-report record of hemolytic anemia (adverse outcome, not a nutrient deficiency)

ATP production: no ampicillin ATP measurement; reduced ATP production reported for piperacillin in human neurons (CLASS EXTRAPOLATION); ampicillin did not produce the apoptosis seen with the energy-crisis drugs

Claims checked and not supported

B vitamins (B12, folate, biotin) lost through reduced gut-flora synthesis (provisional, tooling-limited)

"Antibiotics cause vitamin K deficiency, so ampicillin causes bleeding through vitamin K" (stated as fact)

Ampicillin "wipes out" or permanently destroys gut flora

Ampicillin damages mitochondria, causes oxidative stress or lowers cellular energy in people

How the body handles this medication

What the research says is worth watching

Overlap map, to prevent double counting

Mitochondrial Burden

Oxidative Stress

Copper and Iron Balance

Gut Microbiome Risk

Oxygen and ATP Output