Penicillin G Sodium side effects: what 1,150 FDA adverse event reports show
Drug class
Not stated in label
Brand names
Penicillin G Potassium
Who reports
1,150 reports · 31% serious · 51 with death outcome · 72% female
Used for
Therapy Penicillin G Potassium Injection, USP is indicated in the treatment of serious infections caused by susceptible strains of the designated microorganisms in the conditions listed below. Appropriate culture and susceptibility tests should be done before treatment in order to isolate and identify organisms causing infection and to determine their susceptibility to penicillin G.
What it is
DESCRIPTION Penicillin G Potassium, USP is a natural penicillin. It is chemically designated 4-Thia-1-azabicyclo[3.2.0]heptane-2-carboxylic acid,3,3-dimethyl-7-oxo-6-[(phenylacetyl)amino]-, monopotassium salt, [2 S -(2α, 5α, 6β)]. It is crystalline.
Boxed warning
None in the current label
Causality screen of the 23 strongest signals
What the badges mean
- Labeled adverse reaction The exact term appears in the label's warnings or adverse-reactions sections: a known, expected effect. The FAERS signal confirms the label rather than discovering anything.
- Labeled (related wording) The label describes this effect under different wording (e.g. 'neutropenia' for 'neutrophil count decreased'). Treated as known.
- Likely indication confounding The term appears in the label's indications: reports probably describe the disease being treated (or its progression), not a drug effect. Classic confounding by indication.
- Reporting / coding artifact An administrative, monitoring or exposure term (product issue, off-label use, 'test normal', overdose...). Not a biological reaction; a high PRR here reflects how reports are coded.
- Lab value / disease marker A laboratory result, investigation or disease-activity marker (antibody positive, CRP abnormal, swollen joint count) not described in the label. These usually mirror the monitored disease or testing protocol rather than a drug effect; not screened further.
- Not in label — unassessed Not found in the label text, not an artifact pattern. This is a genuine candidate for a formal causality assessment (Bradford Hill / WHO-UMC); it has NOT had one here.
Strongest disproportionality signals
Flagged terms (PRR ≥ 2, χ² ≥ 4, n ≥ 10), ranked by PRR; infinite PRRs (no comparator reports) excluded. The EBGM column is a second, shrinkage-based estimate (MGPS) with its 5th percentile EB05 and the BCPNN IC025; a pair flagged by PRR alone is marked PRR-only and should be read as fragile. The strata column recomputes the PRR on serious reports only and flags pairs whose reports are unusually skewed by sex or come mostly from consumers rather than clinicians. 4 further terms are in the interactive explorer. Reaction links open the term's cross-drug page.
| Reaction | Reports | PRR 95% CI · ROR · χ²/p | EBGM EB05 · IC025 | Label screen | Serious-only & strata | Trial cross-check |
|---|---|---|---|---|---|---|
| Arteriosclerosis | 27 | 52.3 36.0–76.0ROR 53.6 · χ² 1,305 / p 4e-286 | 50.4 EB05 36.4 · IC025 +4.1 3/3 methods agree | Not in label — unassessed | serious PRR 98.6 · ♀ 0% (drug 72%) | no trial data cached |
| Drug hypersensitivity | 535 | 50.3 47.3–53.5ROR 93.2 · χ² 25,983 / p <1e-300 | 50.1 EB05 46.6 · IC025 +5.4 3/3 methods agree | Labeled (related wording) related wording | serious PRR 45.9 | no trial data cached |
| Obstructive airways disorder | 28 | 45.8 31.8–66.1ROR 46.9 · χ² 1,180 / p 5e-259 | 44.4 EB05 32.2 · IC025 +4.0 3/3 methods agree | Not in label — unassessed | serious PRR 87.0 · ♀ 9% (drug 72%) | no trial data cached |
| Full blood count abnormal | 26 | 45.0 30.8–65.9ROR 46.0 · χ² 1,074 / p 9e-236 | 43.6 EB05 31.3 · IC025 +4.0 3/3 methods agree | Lab value / disease marker | serious PRR 109.2 · ♀ 0% (drug 72%) | no trial data cached |
| Nodule | 28 | 39.2 27.2–56.5ROR 40.1 · χ² 1,002 / p 3e-220 | 38.2 EB05 27.7 · IC025 +3.9 3/3 methods agree | Not in label — unassessed | serious PRR 110.8 · ♀ 4% (drug 72%) | no trial data cached |
| Vasculitis | 25 | 39.1 26.6–57.7ROR 40.0 · χ² 890 / p 7e-196 | 38.0 EB05 27.1 · IC025 +3.8 3/3 methods agree | Not in label — unassessed | serious PRR 77.0 · ♀ 0% (drug 72%) | no trial data cached |
| Hepatic steatosis | 30 | 29.4 20.7–41.9ROR 30.2 · χ² 795 / p 4e-175 | 28.9 EB05 21.2 · IC025 +3.7 3/3 methods agree | Not in label — unassessed | serious PRR 61.3 · ♀ 96% (drug 72%) | no trial data cached |
| Sleep disorder due to a general medical condition | 25 | 28.2 19.1–41.6ROR 28.8 · χ² 629 / p 5e-139 | 27.6 EB05 19.7 · IC025 +3.5 3/3 methods agree | Not in label — unassessed | serious PRR 102.1 · ♀ 0% (drug 72%) | no trial data cached |
| Hypersensitivity (allergic reaction) | 285 | 28.1 25.4–31.0ROR 37.0 · χ² 7,463 / p <1e-300 | 28.0 EB05 25.3 · IC025 +4.5 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 7.8 · 72% consumer | no trial data cached |
| Pulmonary fibrosis | 27 | 25.8 17.7–37.4ROR 26.4 · χ² 618 / p 1e-136 | 25.3 EB05 18.3 · IC025 +3.5 3/3 methods agree | Not in label — unassessed | serious PRR 47.6 · ♀ 0% (drug 72%) | no trial data cached |
| Haemoptysis | 28 | 18.3 12.7–26.3ROR 18.7 · χ² 440 / p 6e-98 | 18.0 EB05 13.0 · IC025 +3.2 3/3 methods agree | Not in label — unassessed | serious PRR 37.6 · ♀ 0% (drug 72%) | no trial data cached |
| Contraindicated product administered | 27 | 16.3 11.2–23.7ROR 16.7 · χ² 373 / p 2e-83 | 16.0 EB05 11.4 · IC025 +3.0 3/3 methods agree | Reporting / coding artifact | serious PRR 37.2 · ♀ 100% (drug 72%) | no trial data cached |
| Hypothyroidism | 28 | 16.0 11.1–23.1ROR 16.4 · χ² 380 / p 6e-85 | 15.7 EB05 11.2 · IC025 +3.0 3/3 methods agree | Not in label — unassessed | serious PRR 32.3 · ♀ 4% (drug 72%) | no trial data cached |
| Anaphylactic reaction (severe allergic reaction) | 47 | 15.6 11.8–20.6ROR 16.2 · χ² 629 / p 5e-139 | 15.4 EB05 12.0 · IC025 +3.3 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 28.5 | no trial data cached |
| Hypoxia (low oxygen) | 28 | 14.6 10.1–21.0ROR 14.9 · χ² 340 / p 3e-76 | 14.2 EB05 10.0 · IC025 +2.9 3/3 methods agree | Not in label — unassessed | serious PRR 27.1 · ♀ 4% (drug 72%) | no trial data cached |
| Carpal tunnel syndrome | 10 | 13.0 7.0–24.1ROR 13.1 · χ² 99 / p 1e-23 | 11.0 EB05 5.5 · IC025 +2.0 3/3 methods agree | Not in label — unassessed | serious PRR 29.3 | no trial data cached |
| Candida infection (yeast infection) | 11 | 12.0 6.7–21.6ROR 12.1 · χ² 100 / p 6e-24 | 10.2 EB05 5.4 · IC025 +2.0 3/3 methods agree | Not in label — unassessed | serious PRR 28.7 | no trial data cached |
| Drug intolerance | 63 | 11.9 9.4–15.2ROR 12.6 · χ² 623 / p 1e-137 | 11.7 EB05 9.4 · IC025 +3.0 3/3 methods agree | Reporting / coding artifact | serious PRR 33.9 · ♀ 100% (drug 72%) | no trial data cached |
| Therapeutic product effect decreased | 29 | 11.9 8.3–17.1ROR 12.2 · χ² 279 / p 5e-63 | 11.4 EB05 8.0 · IC025 +2.7 3/3 methods agree | Reporting / coding artifact | serious PRR 43.0 · ♀ 100% (drug 72%) | no trial data cached |
| Lung disorder | 28 | 10.4 7.2–15.0ROR 10.7 · χ² 230 / p 4e-52 | 9.7 EB05 6.8 · IC025 +2.5 3/3 methods agree | Not in label — unassessed | serious PRR 21.5 · ♀ 9% (drug 72%) | no trial data cached |
| Productive cough (cough with phlegm) | 27 | 10.4 7.2–15.1ROR 10.6 · χ² 220 / p 4e-50 | 9.7 EB05 6.7 · IC025 +2.5 3/3 methods agree | Likely indication confounding shares a disease stem with the indications wording | serious PRR 28.3 · ♀ 5% (drug 72%) | no trial data cached |
| Liver disorder | 25 | 10.3 7.0–15.2ROR 10.5 · χ² 201 / p 7e-46 | 9.5 EB05 6.5 · IC025 +2.5 3/3 methods agree | Not in label — unassessed | serious PRR 21.3 · ♀ 100% (drug 72%) | no trial data cached |
| Cardiac failure congestive | 31 | 7.0 4.9–9.9ROR 7.1 · χ² 153 / p 2e-35 | 6.4 EB05 4.7 · IC025 +2.1 3/3 methods agree | Not in label — unassessed | serious PRR 12.9 · ♀ 96% (drug 72%) | no trial data cached |
Trial evidence (ClinicalTrials.gov)
Most frequently reported reactions
By raw co-report count, regardless of disproportionality. Common terms here are often the illness itself or generic outcomes.
| Reaction | Reports | PRR 95% CI · ROR · χ²/p | EBGM EB05 · IC025 | Label screen | Serious-only & strata | Trial cross-check |
|---|---|---|---|---|---|---|
| Drug hypersensitivity | 535 | 50.3 47.3–53.5ROR 93.2 · χ² 25,983 / p <1e-300 | 50.1 EB05 46.6 · IC025 +5.4 3/3 methods agree | Labeled (related wording) related wording | serious PRR 45.9 | no trial data cached |
| Hypersensitivity (allergic reaction) | 285 | 28.1 25.4–31.0ROR 37.0 · χ² 7,463 / p <1e-300 | 28.0 EB05 25.3 · IC025 +4.5 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 7.8 · 72% consumer | no trial data cached |
| Drug intolerance | 63 | 11.9 9.4–15.2ROR 12.6 · χ² 623 / p 1e-137 | 11.7 EB05 9.4 · IC025 +3.0 3/3 methods agree | Reporting / coding artifact | serious PRR 33.9 · ♀ 100% (drug 72%) | no trial data cached |
| Anaphylactic reaction (severe allergic reaction) | 47 | 15.6 11.8–20.6ROR 16.2 · χ² 629 / p 5e-139 | 15.4 EB05 12.0 · IC025 +3.3 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 28.5 | no trial data cached |
| Cardiac failure congestive | 31 | 7.0 4.9–9.9ROR 7.1 · χ² 153 / p 2e-35 | 6.4 EB05 4.7 · IC025 +2.1 3/3 methods agree | Not in label — unassessed | serious PRR 12.9 · ♀ 96% (drug 72%) | no trial data cached |
| Hepatic steatosis | 30 | 29.4 20.7–41.9ROR 30.2 · χ² 795 / p 4e-175 | 28.9 EB05 21.2 · IC025 +3.7 3/3 methods agree | Not in label — unassessed | serious PRR 61.3 · ♀ 96% (drug 72%) | no trial data cached |
| Therapeutic product effect decreased | 29 | 11.9 8.3–17.1ROR 12.2 · χ² 279 / p 5e-63 | 11.4 EB05 8.0 · IC025 +2.7 3/3 methods agree | Reporting / coding artifact | serious PRR 43.0 · ♀ 100% (drug 72%) | no trial data cached |
| Lung disorder | 28 | 10.4 7.2–15.0ROR 10.7 · χ² 230 / p 4e-52 | 9.7 EB05 6.8 · IC025 +2.5 3/3 methods agree | Not in label — unassessed | serious PRR 21.5 · ♀ 9% (drug 72%) | no trial data cached |
| Hypoxia (low oxygen) | 28 | 14.6 10.1–21.0ROR 14.9 · χ² 340 / p 3e-76 | 14.2 EB05 10.0 · IC025 +2.9 3/3 methods agree | Not in label — unassessed | serious PRR 27.1 · ♀ 4% (drug 72%) | no trial data cached |
| Hypothyroidism | 28 | 16.0 11.1–23.1ROR 16.4 · χ² 380 / p 6e-85 | 15.7 EB05 11.2 · IC025 +3.0 3/3 methods agree | Not in label — unassessed | serious PRR 32.3 · ♀ 4% (drug 72%) | no trial data cached |
| Haemoptysis | 28 | 18.3 12.7–26.3ROR 18.7 · χ² 440 / p 6e-98 | 18.0 EB05 13.0 · IC025 +3.2 3/3 methods agree | Not in label — unassessed | serious PRR 37.6 · ♀ 0% (drug 72%) | no trial data cached |
| Nodule | 28 | 39.2 27.2–56.5ROR 40.1 · χ² 1,002 / p 3e-220 | 38.2 EB05 27.7 · IC025 +3.9 3/3 methods agree | Not in label — unassessed | serious PRR 110.8 · ♀ 4% (drug 72%) | no trial data cached |
| Obstructive airways disorder | 28 | 45.8 31.8–66.1ROR 46.9 · χ² 1,180 / p 5e-259 | 44.4 EB05 32.2 · IC025 +4.0 3/3 methods agree | Not in label — unassessed | serious PRR 87.0 · ♀ 9% (drug 72%) | no trial data cached |
| Productive cough (cough with phlegm) | 27 | 10.4 7.2–15.1ROR 10.6 · χ² 220 / p 4e-50 | 9.7 EB05 6.7 · IC025 +2.5 3/3 methods agree | Likely indication confounding shares a disease stem with the indications wording | serious PRR 28.3 · ♀ 5% (drug 72%) | no trial data cached |
| Contraindicated product administered | 27 | 16.3 11.2–23.7ROR 16.7 · χ² 373 / p 2e-83 | 16.0 EB05 11.4 · IC025 +3.0 3/3 methods agree | Reporting / coding artifact | serious PRR 37.2 · ♀ 100% (drug 72%) | no trial data cached |
Unlabeled candidate signals
These flagged terms were not found in the FDA label text and do not match an artifact pattern. They are the pairs that would merit a structured assessment (temporality, dose-response, biological plausibility, consistency across databases, trial or cohort evidence). The screen has not done that; string-matching misses label wording, and a strong PRR can still be stimulated reporting, co-medication, or the disease itself.
- Arteriosclerosis — n=27, PRR 52.3
- Obstructive airways disorder — n=28, PRR 45.8
- Nodule — n=28, PRR 39.2
- Vasculitis — n=25, PRR 39.1
- Hepatic steatosis — n=30, PRR 29.4
- Sleep disorder due to a general medical condition — n=25, PRR 28.2
- Pulmonary fibrosis — n=27, PRR 25.8
- Haemoptysis — n=28, PRR 18.3
- Hypothyroidism — n=28, PRR 16.0
- Hypoxia — n=28, PRR 14.6
Want to assess one of these properly? The runbook describes the Bradford Hill / trial-evidence workflow used on the assessment page, and handoff_top1000_signals.csv lists the strongest unassessed pairs across all drugs.
Common questions
What are the most reported side effects of Penicillin G?
In FDA FAERS, the most frequently co-reported reaction terms for Penicillin G are drug hypersensitivity, hypersensitivity, anaphylactic reaction, cardiac failure congestive, hepatic steatosis, lung disorder. These are report counts, not rates: FAERS has no denominator, reporting is voluntary and uneven, and a term can be reported because of the illness being treated rather than the drug.
Does Penicillin G have an FDA boxed warning?
No. The FDA label retrieved for Penicillin G has no boxed warning; see the label's Warnings and Precautions for the recognised risks.
Do FAERS signals prove that Penicillin G causes these side effects?
No. A disproportionality signal (PRR, ROR) means a reaction is reported more often with this drug than with others in the database. That can reflect a real effect, but also the disease being treated, stimulated reporting after news or litigation, co-medications, or how reports are coded. Causality needs temporality, dose-response, biological plausibility, consistency across data sources and, ideally, trial or cohort evidence. This page screens each term against the FDA label and ClinicalTrials.gov results; it does not establish causation.
Sources & methods
- FDA label via openFDA (set ID 9e58122f-5c75-4905-a774-d3a4dae4ff8c, effective 20260724; matched on
openfda.generic_name.exact:"PENICILLIN G") - Bayesian shrinkage measures computed offline over all 1,317,300 cached pairs: BCPNN information component (IC, with Norén closed-form IC025) and MGPS empirical-Bayes geometric mean (EBGM, EB05) with a two-component gamma prior fitted by maximum marginal likelihood (α₁=0.57, β₁=0.02, α₂=1.42, β₂=0.70, w=0.17); unstratified
- FAERS pair statistics from the OpenPV build of 2026-09-14 (openFDA
count=aggregation, fieldpatient.drug.openfda.generic_name.exact, 27 reaction terms, min 3 co-reports); PRR/ROR with 95% CI, chi-square with Yates correction - Serious-only and stratified counts (serious:1, patient.patientsex, primarysource.qualification) from openFDA count queries; serious-only PRR uses the drug serious report total and the term global serious total (N_serious=11,882,979); strata shown only when n ≥ 20
- Seriousness and sex counts from openFDA
count=serious,patient.patientsex,seriousnessdeath
Page generated 2026-10-08. Label and PubChem text are retrieved automatically and may lag the current label; always check the current prescribing information. OpenPV is a beta research tool of the Open Source Medicine Foundation.