Reported Reactions

Drugs › Macrolide antimicrobial

Brand name · Azithromycin dihydrate

Zithromax: adverse event reports filed with FDA

7,379 reports list it as a suspect or interacting product, 2004–2026. Class: Macrolide antimicrobial.

7,379
reports as suspect product
0% of all reports · about 328 a year
130
reports, 12 months to June 2026
149 in the 12 months before
56.2%
marked serious by the reporter
82.7% across the class
4.5%
record death among outcomes, as reported
335 reports · not verified by FDA

Between January 2004 and June 2026, 7,379 adverse event reports received by FDA list the brand name Zithromax (azithromycin dihydrate) as a suspect or interacting product. Reports that mention it only as a concomitant medication (10,492) are left out of every figure here.

In the 12 months to June 2026, 130 reports listed it, down 13% from 149 in 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 328 reports a year and 0% of the 20,646,523 reports in the database, and 15.2% of the reports for the macrolide antimicrobial class. How many people take it is not in the data, so a count is not a rate of occurrence.

The reactions recorded most often are drug hypersensitivity (25.1%), drug ineffective (6.6%) and rash (5.7%). A report can list several reactions, so shares add to more than 100%; 1,026 different terms appear across these reports. Drug hypersensitivity is recorded in 25.1% of these reports, a larger share than in the median macrolide antimicrobial drug (3.3%).

56.2% of the reports are marked serious by the reporter (82.7% across the class); 4.5% record death among the outcomes and 22.2% record hospitalisation, as reported. 32.2% of the reports came from physicians, and the largest patient age group is 45 to 64 (18.5%). 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

01835Jul 2021: 14Aug 2021: 16Sep 2021: 8Oct 2021: 20Nov 2021: 16Dec 2021: 182022Jan 2022: 16Feb 2022: 6Mar 2022: 13Apr 2022: 14May 2022: 19Jun 2022: 11Jul 2022: 14Aug 2022: 7Sep 2022: 19Oct 2022: 10Nov 2022: 17Dec 2022: 132023Jan 2023: 16Feb 2023: 18Mar 2023: 16Apr 2023: 11May 2023: 16Jun 2023: 16Jul 2023: 20Aug 2023: 20Sep 2023: 19Oct 2023: 12Nov 2023: 22Dec 2023: 212024Jan 2024: 35Feb 2024: 28Mar 2024: 22Apr 2024: 14May 2024: 10Jun 2024: 14Jul 2024: 16Aug 2024: 11Sep 2024: 12Oct 2024: 10Nov 2024: 15Dec 2024: 102025Jan 2025: 16Feb 2025: 7Mar 2025: 17Apr 2025: 14May 2025: 16Jun 2025: 5Jul 2025: 12Aug 2025: 15Sep 2025: 5Oct 2025: 9Nov 2025: 8Dec 2025: 132026Jan 2026: 16Feb 2026: 7Mar 2026: 13Apr 2026: 9May 2026: 12Jun 2026: 11

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

03016022004: 33320042005: 3182006: 2832007: 17520072008: 2312009: 1992010: 60220102011: 3252012: 3632013: 39120132014: 4552015: 4712016: 48720162017: 4092018: 4862019: 41820192020: 3882021: 2772022: 15920222023: 2072024: 1972025: 13720252026: 68

2026 covers reports received through June 2026 only.

Reactions recorded in the reports

share of Zithromax reports recording the termmedian drug in macrolide antimicrobial

  1. Drug hypersensitivityan allergic-type reaction to a medicine25.1%1,851
  2. Drug ineffectivethe medicine did not work as expected6.6%488
  3. Rashskin rash5.7%421
  4. Diarrhoealoose or frequent stools5.3%389
  5. Off label useused for a purpose or in a way not on the label5.1%374
  6. Dyspnoeashortness of breath4.8%356
  7. Nauseafeeling sick4.5%334
  8. Vomitingbeing sick4.5%331
  9. Urticariahives3.7%270
  10. Pruritusitching3.3%240
  11. Drug interactionan interaction between medicines3.1%232
  12. Malaisegeneral feeling of being unwell3.1%226
  13. Coughcough2.8%203
  14. Pyrexiafever2.5%183
  15. Hypersensitivityan allergic-type reaction2.5%182
  16. Fatiguetiredness2.4%180
  17. Headachehead pain2.3%170
  18. Dizzinesslight-headedness or unsteadiness2.3%169
  19. Pneumonialung infection2.2%165
  20. Abdominal painstomach or belly pain2.2%162
  21. Asthmaasthma2%145
  22. Wheezingwheezing1.8%131
  23. Astheniaweakness or lack of energy1.7%127
  24. Abdominal pain upperupper stomach pain1.7%124
  25. Painpain, site not specified1.7%124
  26. Abdominal discomfortstomach discomfort1.7%123
  27. Palpitationsawareness of the heartbeat1.5%113
  28. Condition aggravatedthe condition being treated got worse1.5%110
  29. Chest painchest pain1.5%109
  30. Feeling abnormalfeeling odd or not right1.5%108

Top 30 of 1,026 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 5 drugs in the macrolide antimicrobial 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

Death4.5%335
Life-threatening3.6%265
Hospitalisation (initial or prolonged)22.2%1,641
Disability2.1%158
Congenital anomaly0.5%35
Other serious37.5%2,770
Not serious43.8%3,232

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 48,453 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

Patient age

Under 22%147
2 to 116.9%510
12 to 172.6%190
18 to 4413.9%1,028
45 to 6418.5%1,367
65 to 7410.6%783
75 and over8.3%614
Age not given37.1%2,740

Patient sex

Female61%4,499
Male29.7%2,195
Not given9.3%685

Who reported

Physician32.2%2,377
Pharmacist8.5%629
Other health professional21.1%1,554
Lawyer0.8%61
Consumer or non-health professional31.3%2,309
Not given6.1%449

Age and sex as stated in the report; the reporter's qualification is the primary source recorded by FDA. 62.7% of reports give the United States as the country of the event or reporter.

Reason for use recorded

Indication as recorded (MedDRA)ReportsShare
Pneumonia3715%
Bronchitis3454.7%
Sinusitis2663.6%
Upper respiratory tract infection1762.4%
Ill-defined disorder1351.8%
Infection1331.8%

The indication field is filled in by the reporter and is often blank; shares are of all 7,379 reports.

Drugs most often listed in the same reports

Drug (any role in the report)ReportsShare of Zithromax reports
Prednisone2443.3%
Bactrim1652.2%
Codeine1612.2%
Levaquin1592.2%
Aspirin1552.1%
Augmentin1331.8%
Amoxicillin1321.8%
Erythromycin1211.6%
Lipitor1061.4%
Morphine sulfate991.3%

Other products listed in reports where Zithromax 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

MeasureZithromaxMacrolide antimicrobialAll reports
Reports as suspect product7,37948,45320,646,523
Share of that pool—15.2%0%
Reports, latest 12 months130—1,332,454
Marked serious56.2%82.7%57.4%
Death recorded among outcomes, per 1,000 reports457291
Hospitalisation recorded, per 1,000 reports222351213
Consumer-filed share31.3%20.8%45.8%
Top term, share of reportsDrug hypersensitivity 25.1%median 3.3%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."

Other drugs in the macrolide antimicrobial class

DrugName typeReportsLatest 12 monthsMarked serious
Clarithromycingeneric21,8141,04495%
Azithromycingeneric17,5002,07082.5%
Azasitebrand1,03587.1%
Azithromycin dihydrategeneric7256897.7%

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.

Questions about Zithromax reports

How many adverse event reports has FDA received for Zithromax?

7,379 reports list Zithromax as a suspect or interacting product in the openFDA FAERS release of 28 Sep 2026, covering reports received through June 2026. 130 of them arrived in the latest 12 months. Another 10,492 list it only as a concomitant medication.

What reactions are recorded in Zithromax reports?

drug hypersensitivity (25.1%), drug ineffective (6.6%), rash (5.7%), diarrhoea (5.3%) and off label use (5.1%). 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 Zithromax was responsible.

How serious are the reports?

56.2% are marked serious by the reporter. Among the outcomes recorded, 4.5% of reports include death and 22.2% 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?

physician (32.2%), consumer or non-health professional (31.3%) and other health professional (21.1%). Most reports reach FDA through the manufacturer, which must forward reports it receives.

Are reports for Zithromax rising?

130 reports in the 12 months to June 2026, down 13% from 149 in 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 Zithromax 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 Zithromax?

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 Zithromax as a suspect or interacting product; reports listing it only as a concomitant medication (10,492) 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.