Unasyn: adverse event reports filed with FDA

773

reports as suspect product

0% of all reports · about 34 a year

22

reports, 12 months to June 2026

18 in the 12 months before

90.9%

marked serious by the reporter

81% across the class

13.6%

record death among outcomes, as reported

105 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 Unasyn reports recording the termmedian drug in penicillin-class antibacterial

1. Rashskin rash6%46
2. Pyrexiafever5%39
3. Drug ineffectivethe medicine did not work as expected4.1%32
4. Pneumonialung infection4.1%32
5. Drug hypersensitivityan allergic-type reaction to a medicine4%31
6. Pruritusitching4%31
7. Hepatic function abnormal3.6%28
8. Diarrhoealoose or frequent stools3.2%25
9. Alanine aminotransferase increasedraised liver enzyme (ALT)3%23
10. Dyspnoeashortness of breath2.8%22
11. Anaphylactic shocka severe allergic reaction with collapse2.7%21
12. Aspartate aminotransferase increasedraised liver enzyme (AST)2.7%21
13. Erythemaskin redness2.7%21
14. Hypotensionlow blood pressure2.3%18
15. Toxic epidermal necrolysisa severe skin reaction with peeling2.1%16
16. Urticariahives1.9%15
17. Drug eruption1.8%14
18. Interstitial lung diseasescarring or inflammation of lung tissue1.8%14
19. Anaphylactic reactiona severe, sudden allergic reaction1.7%13
20. Vomitingbeing sick1.7%13
21. Cellulitisa skin infection1.4%11
22. Renal failure acute1.4%11
23. Chest painchest pain1.3%10
24. Disseminated intravascular coagulation1.3%10
25. Stevens-Johnson syndromea severe skin and mucous-membrane reaction1.3%10
26. Angioedemadeep swelling of skin or mucous membranes1.2%9
27. Blood lactate dehydrogenase increased1.2%9
28. Convulsion1.2%9
29. Liver disorder1.2%9
30. Sepsisa severe body-wide response to infection1.2%9

Top 30 of 223 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. 17.9% 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 773 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 Unasyn as a suspect or interacting product; reports listing it only as a concomitant medication (960) 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.