OVERVIEW

Ampicillin is an oral, third generation aminopenicillin and is used widely to treat mild-to-severe infections due to susceptible organisms. Ampicillin has been linked with idiosyncratic liver injury, but very rarely and largely in isolated case reports.

PRODUCT INFORMATION

REPRESENTATIVE TRADE NAMES

Ampicillin – Generic, Principen®

DRUG CLASS

Antiinfective Agents

COMPLETE LABELING

Product labeling at DailyMed, National Library of Medicine, NIH

CHEMICAL FORMULA AND STRUCTURE

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DRUG	CAS REGISTRY NO	MOLECULAR FORMULA	STRUCTURE
Ampicillin	69-53-4	C16-H19-N3-O4-S

ANNOTATED BIBLIOGRAPHY

References updated: 24 January 2026

• Zimmerman HJ. Penicillins. In, Hepatotoxicity: the adverse effects of drugs and other chemicals on the liver. 2nd ed. Philadelphia: Lippincott Williams and Wilkins, 1999. p. 595-6.

  (Expert review of penicillins and liver injury published in 1999; the penicillins commonly lead to hypersensitivity reactions but rarely to liver injury).
• Moseley RH. Hepatotoxicity of antimicrobials and antifungal agents. In, Kaplowitz N, DeLeve LD, eds. Drug-induced liver disease. 3rd ed. Amsterdam: Elsevier, 2013, pp. 463-82.

  (Review of hepatotoxicity of antibiotics mentions that penicillins rarely cause liver injury and both hepatocellular and cholestatic patterns of injury have been described).
• MacDougall C. Penicillins, cephalosporins, and other β-lactam antibiotics. In, Brunton LL, Hilal-Dandan R, Knollman BC, eds. Goodman & Gilman’s the pharmacological basis of therapeutics. 13th ed. New York: McGraw-Hill, 2018, pp. 1023-38.

  (Textbook of pharmacology and therapeutics).
• Knirsch AK, Gralla EJ. Abnormal serum transaminase levels after parenteral ampicillin and carbenicillin administration. N Engl J Med 1970; 282: 1081-2. [PubMed: 5438429]

  (Elevations in AST and CPK, but not ALT, occurred after intramuscular injections of ampicillin and carbenicillin, but not after cephalosporins or saline; thus, the elevations probably reflected muscle rather than liver injury).
• McArthur JE, Dyment PG. Stevens-Johnson syndrome with hepatitis following therapy with ampicillin and cephalexin. N Z Med J 1975; 81: 390-2. [PubMed: 1057088]

  (Stevens-Johnson syndrome developed in a 9 month old child given ampicillin [rash] and cephalexin, with subsequent hepatocellular injury [bilirubin 13 mg/dL], resolving with prednisone therapy).
• Tamarkina AD, Dement'eva ES, Krylova NI, Minasova GS, Kuleshova EE. [Enzymological evaluation of the hepatotoxicity of ampicillin and its therapeutic form, roscillin, in the treatment of pyelonephritis in pregnancy] Antibiot Med Biotekhnol 1985; 30: 62-4. Russian. [PubMed: 3994343]

  (Prospective analysis of serum enzyme levels in 12 patients receiving ampicillin found no changes during 12 days of therapy, although minor changes occurred when it was stopped).
• Lees L, Milson JA, Knirsch AK, Greenhalgh K. Sulbactam plus ampicillin: interim review of efficacy and safety for therapeutic and prophylactic use. Rev Infect Dis 1986; 8 (Suppl 5): S644-S650. [PubMed: 3026019]

  (Review of 45 studies of ampicillin-sulbactam in 899 patients found successful outcome in 92%; ALT elevations in 6.9%, AST in 6.2%, but all resolved with stopping and similar rates were reported with use of comparative agents).
• Galante D, Esposito S, Barba D, Ruffilli MP. Clinical efficacy and safety of sulbactam/ampicillin in patients suffering from chronic liver disease. J Antimicrob Chemother 1987; 19: 527-32. [PubMed: 3034850]

  (41 patients with advanced liver disease were given ampicillin-sulbactam: there was no worsening of liver disease or enzyme elevations attributed to medication).
• Cavanzo FJ, Garcia CF, Botero RC. Chronic cholestasis, paucity of bile ducts, red cell aplasia, and the Stevens-Johnson syndrome. An ampicillin-associated case. Gastroenterology 1990; 99: 854-6. [PubMed: 2116345]

  (A 35 year old woman developed Stevens-Johnson syndrome with cholestatic hepatitis and red cell aplasia 4 days after starting oral ampicillin and subsequently developed vanishing bile duct syndrome and prolonged cholestasis, but with gradual ultimate improvement after several years).
• Friis H, Andreasen PB. Drug-induced hepatic injury: an analysis of 1100 cases reported to the Danish Committee on Adverse Drug Reactions between 1978 and 1987. J Intern Med 1992; 232: 133-8. [PubMed: 1506809]

  (Adverse drug reaction reports in Denmark from 1978 to 1987; no mention of aminopenicillins).
• Köklü S, Yüksel O, Filik L, Usküdar O, Altundag K, Altiparmak E. Recurrent cholestasis due to ampicillin. Ann Pharmacother 2003; 37: 395-7. [PubMed: 12639171]

  (23 year old man had recurrent bouts of liver injury 12, 8, and 5 days after starting three 7 day courses of ampicillin, last episode marked by bilirubin 2.1 mg/dL, ALT 265 U/L, and Alk P 455 U/L, resolving within 10 days of stopping).
• Köklü S, Yüksel O, Yolcu OF, Arhan M, Altiparmak E. Cholestatic attack due to ampicillin and cross-reactivity to cefuroxime. Ann Pharmacother 2004; 38: 1539-40. [PubMed: 15266040]

  (Follow up on 23 year old man in previous report, who redeveloped liver injury 17 days after starting a 10 day course of cefuroxime [bilirubin 0.7 mg/dL, ALT 427 U/L, Alk P 646 U/L], resolving within 2 months, suggesting cross sensitivity to hepatic injury between cephalosporins and ampicillin).
• Köklü S, Köksal AS, Asil M, Kiyici H, Coban S, Arhan M. Probable sulbactam/ampicillin-associated prolonged cholestasis. Ann Pharmacother 2004; 38: 2055-8. [PubMed: 15494387]

  (74 year old developed cholestatic hepatitis arising 1 week after 7 day course of ampicillin-sulbactam with prolonged jaundice [bilirubin 31 mg/dL, ALT 33 U/L, Alk P 519 U/L], resolving after 7 months, except mild GGT elevations).
• Russo MW, Galanko JA, Shrestha R, Fried MW, Watkins P. Liver transplantation for acute liver failure from drug-induced liver injury in the United States. Liver Transpl 2004; 10: 1018-23. [PubMed: 15390328]

  (Among ~50,000 liver transplants done in the US between 1990 and 2002, 270 [0.5%] were done for drug induced acute liver failure; one case was attributed to amoxicillin-clavulanate, but none to penicillin, ampicillin or amoxicillin alone).
• Chalasani N, Fontana RJ, Bonkovsky HL, Watkins PB, Davern T, Serrano J, Yang H, Rochon J; Drug Induced Liver Injury Network (DILIN). Causes, clinical features, and outcomes from a prospective study of drug-induced liver injury in the United States. Gastroenterology 2008; 135: 1924-34. [PMC free article: PMC3654244] [PubMed: 18955056]

  (Among 300 cases of drug induced liver disease in the US collected from 2004 to 2008, 23 cases were attributed to amoxicillin-clavulanate, 2 cases to amoxicillin, but none to ampicillin).
• Björnsson E, Davidsdottir L. The long-term follow-up after idiosyncratic drug-induced liver injury with jaundice. J Hepatol 2009; 50: 511-7. [PubMed: 19155082]

  (Among 685 patients identified an average of 10 years after an episode of drug induced liver injury, 23 [3.4%] had continuing liver disease, 8 with cirrhosis; one patient who died of cirrhosis had liver injury attributed to ampicillin 3 years previously).
• Devarbhavi H, Dierkhising R, Kremers WK, Sandeep MS, Karanth D, Adarsh CK. Single-center experience with drug-induced liver injury from India: causes, outcome, prognosis, and predictors of mortality. Am J Gastroenterol 2010; 105: 2396-404. [PubMed: 20648003]

  (313 cases of drug induced liver injury were seen over a 12 year period at a large hospital in Bangalore, India; 3 [1%] were attributed to amoxicillin-clavulanate, but none were attributed to ampicillin or amoxicillin alone].
• Reuben A, Koch DG, Lee WM; Acute Liver Failure Study Group. Drug-induced acute liver failure: results of a U.S. multicenter, prospective study. Hepatology 2010; 52: 2065-76. [PMC free article: PMC3992250] [PubMed: 20949552]

  (Among 1198 patients with acute liver failure enrolled in a US prospective study between 1998 and 2007, 133 were attributed to drug induced liver injury including 66 due to antimicrobial agents, including two attributed to amoxicillin but none to ampicillin; no details given).
• Ferrajolo C, Capuano A, Verhamme KM, Schuemie M, Rossi F, Stricker BH, Sturkenboom MC. Drug-induced hepatic injury in children: a case/non-case study of suspected adverse drug reactions in VigiBase. Br J Clin Pharmacol 2010; 70: 721-8. [PMC free article: PMC2997312] [PubMed: 21039766]

  (Worldwide pharmacovigilance database contained 9036 hepatic adverse drug reactions in children, amoxicillin-clavulanate accounted for 38 cases [0.4%] for an adjusted odds ratio of 1.7, whereas neither amoxicillin or ampicillin alone were listed among the 41 most common causes [linked to at least 30 cases]).
• Köksal AS, Yildiz H, Onder O, Avci S, Kayaåetin E. Sulbactam/ampicillin associated hepatocellular type liver injury. Acta Gastroenterol Belg 2012; 75: 66-7. [PubMed: 22567755]

  (47 year old woman developed jaundice 8 days after a 4 day course of ampicillin-sulbactam [bilirubin 18.9 mg/dL, ALT 1344 U/L, Alk P 208 U/L], resolving within 10 weeks of stopping).
• Björnsson ES, Bergmann OM, Björnsson HK, Kvaran RB, Olafsson S. Incidence, presentation and outcomes in patients with drug-induced liver injury in the general population of Iceland. Gastroenterology 2013; 144: 1419-25. [PubMed: 23419359]

  (In a population based study of drug induced liver injury from Iceland, 96 cases were identified over a 2 year period, the most commonly implicated agent being amoxicillin-clavulanate [15 cases]; none were attributed to amoxicillin or ampicillin alone).
• Sistanizad M, Peterson GM. Drug-induced liver injury in the Australian setting. J Clin Pharm Ther 2013; 38: 115-20. [PubMed: 23350857]

  (Among 17 cases of suspected drug induced liver injury seen at a single referral hospital in Tasmania over a 12 month period, 11 were due to antibiotics including flucloxacillin in 4, amoxicillin in 2, amoxicillin-clavulanate in 2, and rifampin, moxifloxacin and ciprofloxacin in 1 each).
• Ferrajolo C, Verhamme KM, Trifirò G, 't Jong GW, Giaquinto C, Picelli G, Oteri A, et al. Idiopathic acute liver injury in paediatric outpatients: incidence and signal detection in two European countries. Drug Saf 2013; 36: 1007-16. [PubMed: 23591830]

  (Analysis of 3 electronic healthcare databases from Italy and the Netherlands from 2000-2008 identified 785 cases of unexplained acute liver injury in children, linked to 110 possible medications, with increased adjusted relative risk [RR] of recent exposure to amoxicillin-clavulanate [RR=18.6] and amoxicillin [RR=7.5]).
• Lim R, Choudry H, Conner K, Karnsakul W. A challenge for diagnosing acute liver injury with concomitant/sequential exposure to multiple drugs: can causality assessment scales be utilized to identify the offending drug? Case Rep Pediatr 2014; 2014: 156389. [PMC free article: PMC4260426] [PubMed: 25506455]

  (12 year old boy was treated with oral ampicillin for suspected Streptococcal sore throat and developed evidence of neck cellulitis and was treated with intravenous ampicillin-sulbactam, vancomycin, and oral clindamycin at which point he developed jaundice [bilirubin 3.0 mg/dL, ALT 406 U/L, Alk P 404 U/L, INR 1.1] and was continued on ampicillin-sulbactam, developing rash and deep and prolonged jaundice and itching which lasted 5 months and resolved, but with persistence of alkaline phosphatase elevations, the causative agent being unclear but most likely ampicillin-sulbactam).
• Kaye JA, Castellsague J, Bui CL, Calingaert B, McQuay LJ, Riera-Guardia N, Saltus CW, et al. Risk of acute liver injury associated with the use of moxifloxacin and other oral antimicrobials: a retrospective, population-based cohort study. Pharmacotherapy 2014; 34: 336-49. [PMC free article: PMC4260122] [PubMed: 24865821]

  (In a US healthcare database with 1.3 million antimicrobial users, there were 607 cases of liver injury and 11 cases of liver failure, the highest relative risk for current single use being 3.2 for levofloxacin, 2.5 for amoxicillin-clavulanate, 2.5 for doxycycline, 2.3 for moxifloxacin, and 2.3 for amoxicillin).
• Hernández N, Bessone F, Sánchez A, di Pace M, Brahm J, Zapata R, A Chirino R, et al. Profile of idiosyncratic drug induced liver injury in Latin America. An analysis of published reports. Ann Hepatol 2014; 13: 231-9. [PubMed: 24552865]

  (Systematic review of literature of drug induced liver injury from Latin American countries published between 1996 and 2012 identified 176 cases, of which 37 [19%] were attributed to antimicrobials, including one to benzathine penicillin and 3 to amoxicillin-clavulanate, but none to other penicillins).
• Chalasani N, Bonkovsky HL, Fontana R, Lee W, Stolz A, Talwalkar J, Reddy KR, et al.; United States Drug Induced Liver Injury Network. Features and outcomes of 899 patients with drug-induced liver injury: The DILIN Prospective Study. Gastroenterology 2015; 148: 1340-52.e7. [PMC free article: PMC4446235] [PubMed: 25754159]

  (Among 899 cases of drug induced liver injury enrolled in a US prospective study between 2004 and 2013, 323 [36%] were attributed to antibiotics of which 106 [12%] were due to penicillins including one to 1st, three to 2nd [all due to oxacillin], 97 to 3rd [91 to amoxicillin-clavulanate, and 6 to amoxicillin alone] and five to 4th generation penicillins [all 5 to piperacillin-tazobactam]; none were attributed to ampicillin).
• Guéant JL, Romano A, Cornejo-Garcia JA, Oussalah A, Chery C, Blanca-López N, Guéant-Rodriguez RM, et al. HLA-DRA variants predict penicillin allergy in genome-wide fine-mapping genotyping. J Allergy Clin Immunol 2015; 135: 253-9. [PubMed: 25224099]

  (In a genome wide association study of 387 patients with immediate allergic reactions to beta-lactam antibiotics, several class 2 HLA associations [HLA-DRA regions] were found for penicillin responses, but they did not apply to cephalosporin cases).
• Björnsson ES. Drug-induced liver injury: an overview over the most critical compounds. Arch Toxicol 2015; 89: 327-34. [PubMed: 25618544]

  (Review of the most common causes of drug induced liver injury in 3 recent surveys, all of which listed amoxicillin-clavulanate as the most frequent cause; none listed other penicillins).
• Blumenthal KG, Youngster I, Rabideau DJ, Parker RA, Manning KS, Walensky RP, Nelson SB. Peripheral blood eosinophilia and hypersensitivity reactions among patients receiving outpatient parenteral antibiotics. J Allergy Clin Immunol 2015; 136: 1288-94.e1. [PMC free article: PMC4640981] [PubMed: 25981739]

  (Among 824 patients who underwent outpatient parenteral antibiotic therapy for at least 2 weeks, 210 [25%] developed eosinophilia including 58 of 207 [28%] who received “penicillins” of whom 3 developed signs of “possible” DRESS syndrome; specific penicillins accounting for the cases were not provided).
• Nicoletti P, Aithal GP, Bjornsson ES, Andrade RJ, Sawle A, Arrese M, Barnhart HX, et al.; International Drug-Induced Liver Injury Consortium, Drug-Induced Liver Injury Network Investigators, and International Serious Adverse Events Consortium. Association of liver injury from specific drugs, or groups of drugs, with polymorphisms in HLA and other genes in a genome-wide association study. Gastroenterology 2017; 152: 1078-89. [PMC free article: PMC5367948] [PubMed: 28043905]

  (A genome wide association study done on 862 Caucasian patients with drug induced liver injury demonstrated a strong link with HLA-A*33:01 in those with cholestatic liver injury, particularly in cases attributed to terbinafine, fenofibrate and ticlopidine).
• Munz M, Grummich H, Birkmann J, Wilhelm M, Holzgrabe U, Sörgel F. Severe drug-Induced liver injury as an adverse drug event of antibiotics: a case report and review of the literature. Chemotherapy 2017; 62: 367-73. [PubMed: 28934748]

  (20 year old woman received 4 antibiotics [amoxicillin, ciprofloxacin, cefazolin, and clindamycin] and acetaminophen within weeks of developing rash, fever and jaundice [bilirubin 3.7 mg/dL, ALT 1219 U/L, Alk P 143 U/L, GGT 201 U/L, INR 1.6], with worsening and signs of hepatic failure but subsequent spontaneous and complete resolution, the specific cause being obscure because of polypharmacy).
• Takeuchi Y, Shinozaki T, Kumamaru H, Hiramatsu T, Matsuyama Y. Analyzing intent-to-treat and per-protocol effects on safety outcomes using a medical information database: an application to the risk assessment of antibiotic-induced liver injury. Expert Opin Drug Saf 2018; 17: 1071-9. [PubMed: 30252549]

  (Cohort matching of cases with vs without antibiotic therapy in a large electronic medical record database from the University of Tokyo Hospital from 2011 to 2015 with adjustments found rates of liver test abnormalities within 30 days of starting penicillins [25.2 per 1000] was higher than that with fluoroquinolones [11.4], macrolide antibiotics [8.1], as well as controls [6.5 to 7.1]).
• Cirulli ET, Nicoletti P, Abramson K, Andrade RJ, Bjornsson ES, Chalasani N, Fontana RJ, et al.; Drug-Induced Liver Injury Network (DILIN) investigators; International DILI consortium (iDILIC). A missense variant in PTPN22 is a risk factor for drug-induced liver injury. Gastroenterology 2019; 156: 1707-16.e2. [PMC free article: PMC6511989] [PubMed: 30664875]

  (Genome wide association studies on 2048 patients with drug induced liver injury and 12,439 controls identified a variant in PTPN22 which was highly associated with liver injury, allele frequency being 0.12 among cases and 0.08 among controls with highest association in Northern Europeans and in cases of amoxicillin clavulanate, PTPN22 being a cellular kinase involved in modulation of immune reactions).
• Alhaddad O, Elsabaawy M, Abdelsameea E, Abdallah A, Shabaan A, Ehsan N, Elrefaey A, et al. Presentations, causes and outcomes of drug-induced liver injury in Egypt. Sci Rep. 2020;10:5124. [PMC free article: PMC7083870] [PubMed: 32198411]

  (Among 75 patients with drug-induced liver injury seen at an Egyptian referral center between 2015 and 2016, 56 [71%] were in patients with chronic hepatitis C, and the most common causes were diclofenac [41%], amoxicillin-clavulanate [19%], halothane [11%], ibuprofen [5%], and khat [4%]; none were due to ampicillin or other aminopenicillins).
• Suzuki T, Sugiyama E, Nozawa K, Tajima M, Takahashi K, Yoshii M, Suzuki H, et al. Effects of dosing frequency on the clinical efficacy of ampicillin/sulbactam in Japanese elderly patients with pneumonia: A single-center retrospective observational study. Pharmacol Res Perspect. 2021;9:e00746. [PMC free article: PMC7992287] [PubMed: 33764686]

  (Among 106 patients 70 years or older with pneumonia treated with intravenous ampicillin-sulbactam in doses of 6 gm given either 2 vs 4 times daily, the clinical response rate was 36% vs 56% while adverse event rates were similar, ALT elevations arising in 16% of both groups which were above 3 times ULN in 1 vs 2 participants and with no episodes of clinically apparent liver injury).
• Guo YM, Ge FL, Song HB, Xiong P, Jing J, Niu M, Zhao X, et al. Relative risk analysis of liver-related adverse drug reactions in children based on China's National Spontaneous Reporting System. J Pediatr. 2021;234:85-91. [PubMed: 33794217]

  (Among 1206 pediatric liver related adverse events reported to the China National Spontaneous Reporting System, the most frequently implicated agents were anti-tuberculosis agents [283 cases], methotrexate [140], and azithromycin [130], while amoxicillin-clavulanate was implicated in 22, amoxicillin alone 14, ampicillin 1, ampicillin-sulbactam none).
• Fowler C, Namtu K. Ampicillin-sulbactam-induced liver injury in a pediatric patient. J Pediatr Pharmacol Ther. 2023;28:747-751. [PMC free article: PMC10715387] [PubMed: 38094676]

  (12 year old boy with seizures, developmental delay, and recurrent aspiration pneumonia developed respiratory failure and pleural effusion and was treated with ampicillin-sulbactam [2 gm 4 times daily] and developed worsening liver tests which peaked at day 5 [bilirubin direct/total 0.8/1.2 mg/dL, ALT 1328 U/L, AST 2171 U/L, INR 2.1] which began to resolve with stopping ampicillin-sulbactam, considered the cause although ischemic hepatitis was also likely).
• Nicoletti P, Dellinger A, Li YJ, Barnhart HX, Chalasani N, Fontana RJ, Odin JA, et al; Drug-Induced Liver Injury Network (DILIN); International Drug-Induced Liver Injury Consortium (iDILIC); Prospective European Drug-Induced Liver Injury (Pro-Euro DILI) Investigators. Identification of reduced ERAP2 expression and a novel HLA allele as components of a risk score for susceptibility to liver injury due to amoxicillin-clavulanate. Gastroenterology. 2023;164:454-466. [PMC free article: PMC9974860] [PubMed: 36496055]

  (Genome and transcriptome wide association studies on 444 patients with liver injury from amoxicillin-clavulanate vs 10,397 controls identified 3 HLA region risk alleles [A*02:01, B*14:01, and DRB1*15:01], and 2 non-HLA risk variants [in ERAP2 and PTPN22]; the combination of all 5 being applicable in a sensitive genetic risk score; ampicillin cases were too few and not evaluated)
• Gu S, Rajendiran G, Forest K, Tran TC, Denny JC, Larson EA, Wilke RA. Drug-induced liver injury with commonly used antibiotics in the All of Us Research Program. Clin Pharmacol Ther. 2023;114:404-412. [PMC free article: PMC10484299] [PubMed: 37150941]

  (Among patients enrolled in a prospective study of genetics and health who had been exposed to various drugs, electronic medical records identified 30 attributable to amoxicillin-clavulanate, 22 to amoxicillin, but drugs with fewer than 20 cases, such as ampicillin, were not mentioned).
• Medina-Cáliz I, Sanabria-Cabrera J, Villanueva-Paz M, Aukštikalnė L, Stephens C, Robles-Díaz M, Pinazo-Bandera JM, et al. Characterization of drug-induced liver injury associated with drug reaction with eosinophilia and systemic symptoms in two prospective DILI registries. Arch Toxicol. 2024;98:303-325. [PMC free article: PMC10761448] [PubMed: 38051367]

  (Among 1437 patients enrolled in the Spanish and Latin American registries of drug-induced liver injury, 53 [3.7%] developed DRESS syndrome, the most common causes were carbamazepine [13%], anti-tuberculous agents [13%], amoxicillin-clavulanate [11%], allopurinol [8%], and lamotrigine [8%]: no case of ampicillin developed DRESS).
• Ooi H, Asai Y, Sato Y. Risk evaluation of ampicillin/sulbactam-induced liver injury based on albumin-bilirubin score. J Infect Chemother. 2023;29:900-904.. [PubMed: 37301371]

  (Among 380 patients treated with ampicillin-sulbactam at a single Japanese referral center, 36 [9.5%] developed ALT or Alk P elevations above twice ULN during or shortly after therapy, no mention of symptoms or concurrent bilirubin levels).
• Pinazo-Bandera JM, Niu H, Alvarez-Alvarez I, Medina-Cáliz I, Del Campo-Herrera E, Ortega-Alonso A, Robles-Díaz M, et al. Rechallenge in idiosyncratic drug-induced liver injury: An analysis of cases in two large prospective registries according to existing definitions. Pharmacol Res. 2024;203:107183.. [PubMed: 38631619]

  (Among 1418 patients enrolled in the Spanish and Latin American registries of drug-induced liver injury, 58 had a positive rechallenge response including 10 due to amoxicillin-clavulanate and 1 due to amoxicillin, but no mention of ampicillin or other penicillins).
• Ishikawa K, Kobayashi D, Mori N. Adverse events comparison of double beta-lactam combinations for bloodstream infections: ampicillin plus ceftriaxone and ampicillin/cloxacillin. Antibiotics (Basel). 2024;13:696. [PMC free article: PMC11350733] [PubMed: 39199996]

  (Analysis of adverse events in 277 patients hospitalized with infections receiving ampicillin-sulbactam alone vs 57 receiving it combined with a cephalosporin vs 43 receiving it combined with cloxacillin revealed ALT elevations above 3 times ULN in 9.5% vs 19.3% vs 16.3% which were above 5 times ULN in 3.6% vs 8.8% vs 9.3%; no mention of concurrent bilirubin elevations or clinically apparent liver injury).
• Bessone F, Hernandez N, Medina-Caliz I, García-Cortés M, Schinoni MI, Mendizabal M, Chiodi D, et al. Drug-induced liver injury in Latin America: 10-year experience of the Latin American DILI (LATINDILI) Network. Clin Gastroenterol Hepatol. 2025;23:89-102.. [PubMed: 38992407]

  (Among 483 cases of drug-induced liver injury enrolled in a prospective Latin American database, 58 [14%] were attributed to amoxicillin-clavulanate, 2 [0.5%] to amoxicillin alone, and only 1 to ampicillin; clinical details not given).
• Chen VL, Rockey DC, Bjornsson ES, Barnhart H, Hoofnagle JH; Drug-Induced Liver Injury Network Investigators. Incidence of idiosyncratic drug-induced liver Injury caused by prescription drugs. Drug Saf. 2025;48:151-160. 39317916. [PMC free article: PMC11785493] [PubMed: 39317916]

  (Analysis of 1284 cases of drug-induced liver injury enrolled in a U.S. prospective study, identified 191 cases [15%; incidence 1:2,400] attributed to amoxicillin-clavulanate, but only 15 [1.3%: incidence 1:170,000] to amoxicillin alone, and none to ampicillin).