Penicillin v potassium: adverse event reports filed with FDA

1,285

reports as suspect product

0% of all reports · about 57 a year

63

reports, 12 months to June 2026

56 in the 12 months before

36.3%

marked serious by the reporter

81% across the class

4.6%

record death among outcomes, as reported

59 reports · not verified by FDA

Reports by month, five years

Reports by the month FDA received them. FDA releases FAERS data quarterly, so the newest months are incomplete and grow in later releases.

By year received

2026 covers reports received through June 2026 only.

Reactions recorded in the reports

share of Penicillin v potassium reports recording the termmedian drug in penicillin-class antibacterial

1. Drug hypersensitivityan allergic-type reaction to a medicine41.7%536
2. Hypersensitivityan allergic-type reaction12.5%160
3. Rashskin rash8.1%104
4. Dyspnoeashortness of breath7%90
5. Urticariahives6.8%87
6. Asthmaasthma6.4%82
7. Therapeutic product effect incomplete4.6%59
8. Condition aggravatedthe condition being treated got worse4.4%57
9. Anxietyanxiety4.4%56
10. Hypothyroidismunderactive thyroid4.4%56
11. Obstructive airways disorder4.4%56
12. Wheezingwheezing4.1%53
13. Sleep disorder due to a general medical condition4%52
14. Full blood count abnormal3.9%50
15. Loss of personal independence in daily activities3.9%50
16. Drug ineffectivethe medicine did not work as expected3.8%49
17. Anaphylactic reactiona severe, sudden allergic reaction3.7%48
18. Pruritusitching3.1%40
19. Lung disordera lung problem, type not specified2.7%35
20. Productive cougha cough with phlegm2.7%35
21. Pulmonary embolisma blood clot in the lung2.7%35
22. Pain in extremitypain in an arm or leg2.6%33
23. Eosinophilic granulomatosis with polyangiitis2.3%30
24. Haemoptysiscoughing up blood2.3%30
25. Neuritis2.3%30
26. Neurological symptom2.3%30
27. Pulmonary alveolar haemorrhage2.3%30
28. Pulmonary fibrosis2.3%30
29. Thrombosis2.3%30
30. Antineutrophil cytoplasmic antibody positive2.3%29

Top 30 of 329 MedDRA preferred terms recorded across these reports, with a plain-language gloss where one is available. One report can record several terms. The hollow bar is the median share across the 15 drugs in the penicillin-class antibacterial class; it describes the reports, not the patients. FDA states that adverse event reports "represent a small percentage of total usage numbers of a product", that "common products may have a higher number of adverse events due to the higher total number of people using the product", and that the data "by themselves are not an indicator of the safety profile of the drug or biologic."

Outcomes recorded

Outcome flags as the reporter set them; a report can carry several, and "other serious" is FDA's own category for serious reports outside the named outcomes. Grey bar: all 64,409 reports in the class. FDA has not verified any outcome and states that the reports "cannot be used to estimate the incidence of these events."

Patients and reporters

Age and sex as stated in the report; the reporter's qualification is the primary source recorded by FDA. 72.7% of reports give the United States as the country of the event or reporter.

Reason for use recorded

The indication field is filled in by the reporter and is often blank; shares are of all 1,285 reports.

In context

Shares are of reports, not of patients treated. The number of people taking a product is not in the data, so none of these figures is a rate, and differences between columns reflect who takes a product, who reports and how long it has been sold. FDA states that adverse event reports "represent a small percentage of total usage numbers of a product", that "common products may have a higher number of adverse events due to the higher total number of people using the product", and that the data "by themselves are not an indicator of the safety profile of the drug or biologic."

Other drugs in the penicillin-class antibacterial class

Ordered by report count for navigation only. FDA states that adverse event reports "represent a small percentage of total usage numbers of a product", that "common products may have a higher number of adverse events due to the higher total number of people using the product", and that the data "by themselves are not an indicator of the safety profile of the drug or biologic." A brand and its generic are separate rows because reporters name them separately.

Where this comes from. Counts are built from the openFDA Drug Adverse Event (FAERS) bulk export released 28 Sep 2026, which holds reports FDA received through 30 Jun 2026. Drug names are as reported, resolved to the brand or generic name on the FDA label where openFDA's harmonisation matched them; classes are the pharmacologic class (EPC) from the label and the National Drug Code Directory of 17 Sep 2026. A report counts here when it lists Penicillin v potassium as a suspect or interacting product; reports listing it only as a concomitant medication (1,469) are excluded. No report narrative, lot number, patient detail or reporter identity is published. See the methodology and sources; FDA's record is authoritative, and corrections are handled within five working days.