Reported Reactions

Drugs

Product name as reported

Penicillin: adverse event reports filed with FDA

2,634 reports list it as a suspect or interacting product, 2004–2026. Also reported as Penicillin Nos, Penicillin /00000901/, Penicillin /00001805/.

2,634
reports as suspect product
0% of all reports · about 117 a year
129
reports, 12 months to June 2026
142 in the 12 months before
59.4%
marked serious by the reporter
57.4% across all reports
4.9%
record death among outcomes, as reported
129 reports · not verified by FDA

2,634 adverse event reports received by FDA list the product name "Penicillin" as reporters wrote it as a suspect or interacting product, from January 2004 to June 2026. A further 5,019 reports list it only as a concomitant medication, and those are not counted in the figures on this page.

In the 12 months to June 2026, 129 reports listed it, close to the 142 of the 12 months before. FDA releases FAERS data quarterly, so the newest months are incomplete and grow in later releases. Over its reporting history that is about 117 reports a year and 0% of the 20,646,523 reports in the database. How many people take it is not in the data, so a count is not a rate of occurrence.

Reporters most often recorded drug hypersensitivity (36%), rash (16.7%) and urticaria (12.5%). A report can list several reactions, so shares add to more than 100%; 681 different terms appear across these reports. Drug hypersensitivity is recorded in 36% of these reports, against 0.9% of all reports in the database.

59.4% of the reports are marked serious by the reporter; 4.9% record death among the outcomes and 23.7% record hospitalisation, as reported. 36.5% of the reports came from consumers, and the largest patient age group is 45 to 64 (20%). FDA states that "a causal relationship cannot be established between product and reactions listed in a report" and that for any given report "there is no certainty that a suspected drug caused the event."

Reports by month, five years

04181Jul 2021: 14Aug 2021: 20Sep 2021: 16Oct 2021: 22Nov 2021: 12Dec 2021: 102022Jan 2022: 13Feb 2022: 7Mar 2022: 20Apr 2022: 24May 2022: 14Jun 2022: 17Jul 2022: 14Aug 2022: 12Sep 2022: 5Oct 2022: 10Nov 2022: 13Dec 2022: 132023Jan 2023: 20Feb 2023: 5Mar 2023: 14Apr 2023: 22May 2023: 20Jun 2023: 28Jul 2023: 9Aug 2023: 22Sep 2023: 19Oct 2023: 26Nov 2023: 34Dec 2023: 122024Jan 2024: 14Feb 2024: 22Mar 2024: 81Apr 2024: 61May 2024: 56Jun 2024: 37Jul 2024: 29Aug 2024: 16Sep 2024: 10Oct 2024: 26Nov 2024: 7Dec 2024: 102025Jan 2025: 7Feb 2025: 8Mar 2025: 9Apr 2025: 5May 2025: 10Jun 2025: 5Jul 2025: 9Aug 2025: 12Sep 2025: 19Oct 2025: 16Nov 2025: 12Dec 2025: 62026Jan 2026: 10Feb 2026: 8Mar 2026: 11Apr 2026: 8May 2026: 4Jun 2026: 14

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

01853692004: 2720042005: 282006: 402007: 2720072008: 262009: 202010: 5120102011: 752012: 1152013: 6620132014: 1092015: 1222016: 12220162017: 1372018: 1552019: 16420192020: 1902021: 2252022: 16220222023: 2312024: 3692025: 11820252026: 55

2026 covers reports received through June 2026 only.

Reactions recorded in the reports

share of Penicillin reports recording the termall reports in the database

  1. Drug hypersensitivityan allergic-type reaction to a medicine36%949
  2. Rashskin rash16.7%440
  3. Urticariahives12.5%330
  4. Hypersensitivityan allergic-type reaction8.7%229
  5. Pruritusitching8.5%223
  6. Diarrhoealoose or frequent stools8.2%215
  7. Nauseafeeling sick7.9%207
  8. Drug ineffectivethe medicine did not work as expected7.6%200
  9. Dyspnoeashortness of breath6.3%167
  10. Fatiguetiredness6.3%167
  11. Malaisegeneral feeling of being unwell6%157
  12. Dizzinesslight-headedness or unsteadiness5.5%145
  13. Painpain, site not specified5.2%137
  14. Anaphylactic reactiona severe, sudden allergic reaction5.2%136
  15. Arthralgiajoint pain5.2%136
  16. Abdominal pain upperupper stomach pain5.1%135
  17. Vomitingbeing sick5.1%135
  18. Headachehead pain4.9%128
  19. Pneumonialung infection4.3%112
  20. Hypertensionhigh blood pressure4.1%107
  21. Coughcough4%106
  22. Pyrexiafever3.9%102
  23. Drug intolerancethe medicine was not tolerated3.8%99
  24. Anxietyanxiety3.6%94
  25. Off label useused for a purpose or in a way not on the label3.5%92
  26. Feeling abnormalfeeling odd or not right3.4%89
  27. Abdominal painstomach or belly pain3.2%83
  28. Migrainemigraine3.2%83
  29. Hyperhidrosisexcessive sweating3%79
  30. Abdominal discomfortstomach discomfort2.9%77

Top 30 of 681 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 share of all reports in the database; 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

Death4.9%129
Life-threatening4.5%118
Hospitalisation (initial or prolonged)23.7%625
Disability1.4%38
Congenital anomaly0.2%6
Other serious46%1,212
Not serious40.6%1,069

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 20,646,523 reports. FDA has not verified any outcome and states that the reports "cannot be used to estimate the incidence of these events."

Patients and reporters

Patient age

Under 20.8%20
2 to 112.5%67
12 to 172%52
18 to 4414.7%386
45 to 6420%528
65 to 747.3%191
75 and over6.2%163
Age not given46.6%1,227

Patient sex

Female63.8%1,681
Male23.9%629
Not given12.3%324

Who reported

Physician21.9%577
Pharmacist4.9%129
Other health professional31.8%837
Lawyer0.4%10
Consumer or non-health professional36.5%961
Not given4.6%120

Age and sex as stated in the report; the reporter's qualification is the primary source recorded by FDA. 63.9% of reports give the United States as the country of the event or reporter.

Reason for use recorded

Indication as recorded (MedDRA)ReportsShare
Prophylaxis491.9%
Pharyngitis streptococcal250.9%
Tonsillitis130.5%
Antibiotic therapy110.4%
Tooth infection110.4%
Psoriasis90.3%

The indication field is filled in by the reporter and is often blank; shares are of all 2,634 reports.

Drugs most often listed in the same reports

Drug (any role in the report)ReportsShare of Penicillin reports
Prednisone2027.7%
Codeine1686.4%
Methotrexate1565.9%
Gabapentin1385.2%
Acetaminophen1355.1%
Ciprofloxacin1325%
Clindamycin1294.9%
Amoxicillin1264.8%
Celebrex1064%
Humira1054%

Other products listed in reports where Penicillin is a suspect product, whatever their own role. Co-listing means the two were recorded together; it says nothing about either product's part in the event. Only the 2,500 most-reported names are counted here.

In context

MeasurePenicillinAll reports
Reports as suspect product2,63420,646,523
Share of that pool—0%
Reports, latest 12 months1291,332,454
Marked serious59.4%57.4%
Death recorded among outcomes, per 1,000 reports4991
Hospitalisation recorded, per 1,000 reports237213
Consumer-filed share36.5%45.8%
Top term, share of reportsDrug hypersensitivity 36%0.9%

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."

Questions about Penicillin reports

How many adverse event reports has FDA received for Penicillin?

2,634 reports list Penicillin as a suspect or interacting product in the openFDA FAERS release of 28 Sep 2026, covering reports received through June 2026. 129 of them arrived in the latest 12 months. Another 5,019 list it only as a concomitant medication.

What reactions are recorded in Penicillin reports?

drug hypersensitivity (36%), rash (16.7%), urticaria (12.5%), hypersensitivity (8.7%) and pruritus (8.5%). These are MedDRA preferred terms coded from what the reporter described; a report can list several, and a term's presence is not a finding that Penicillin was responsible.

How serious are the reports?

59.4% are marked serious by the reporter. Among the outcomes recorded, 4.9% of reports include death and 23.7% include hospitalisation. FDA has not verified these outcomes and states that the reports "cannot be used to estimate the incidence" of the events.

Who files these reports?

consumer or non-health professional (36.5%), other health professional (31.8%) and physician (21.9%). Most reports reach FDA through the manufacturer, which must forward reports it receives.

Are reports for Penicillin rising?

129 reports in the 12 months to June 2026, close to the 142 of the 12 months before. FDA releases FAERS data quarterly, so the newest months are incomplete and grow in later releases. Counts also move with how many people take a product, its time on the market and publicity.

Do these reports show that Penicillin was responsible for these reactions?

No. FDA states that "a causal relationship cannot be established between product and reactions listed in a report" and that for any given report "there is no certainty that a suspected drug caused the event." The reaction may relate to the condition being treated, to other medicines, or to something else.

Is this a list of the side effects of Penicillin?

No. It is a count of what was reported to FDA. The adverse reactions observed in clinical studies are printed on the FDA-approved label, which a pharmacist or clinician can go through with you.

How do I report an adverse event?

Consumers and health professionals can report to FDA through MedWatch (Form FDA 3500 online, or 1-800-FDA-1088), or to the manufacturer, which must pass reports on. See the guide on how to report.

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 as a suspect or interacting product; reports listing it only as a concomitant medication (5,019) 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.

Drug data (FAERS) through 30 Jun 2026; device data (MAUDE) through 31 Aug 2026. Not medical advice.