Reported Reactions

Drugs

Product name as reported

Klacid: adverse event reports filed with FDA

893 reports list it as a suspect or interacting product, 2004–2021. Also reported as Klacid /00984601/.

893
reports as suspect product
0% of all reports · about 40 a year
0
reports, 12 months to June 2026
0 in the 12 months before
99.2%
marked serious by the reporter
57.4% across all reports
8.1%
record death among outcomes, as reported
72 reports · not verified by FDA

Between January 2004 and September 2021, 893 adverse event reports received by FDA list the product name "Klacid" as reporters wrote it as a suspect or interacting product. Reports that mention it only as a concomitant medication (337) are left out of every figure here.

In the 12 months to June 2026, 0 reports listed it, and none 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 40 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 interaction (9.5%), dyspnoea (6.2%) and pruritus (5.9%). A report can list several reactions, so shares add to more than 100%; 314 different terms appear across these reports. Drug interaction is recorded in 9.5% of these reports, against 0.8% of all reports in the database.

99.2% of the reports are marked serious by the reporter; 8.1% record death among the outcomes and 49.4% record hospitalisation, as reported. 42.8% of the reports came from physicians, and the largest patient age group is 45 to 64 (23.7%). 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

035Jul 2021: 2Aug 2021: 5Sep 2021: 4Oct 2021: 0Nov 2021: 0Dec 2021: 02022Jan 2022: 0Feb 2022: 0Mar 2022: 0Apr 2022: 0May 2022: 0Jun 2022: 0Jul 2022: 0Aug 2022: 0Sep 2022: 0Oct 2022: 0Nov 2022: 0Dec 2022: 02023Jan 2023: 0Feb 2023: 0Mar 2023: 0Apr 2023: 0May 2023: 0Jun 2023: 0Jul 2023: 0Aug 2023: 0Sep 2023: 0Oct 2023: 0Nov 2023: 0Dec 2023: 02024Jan 2024: 0Feb 2024: 0Mar 2024: 0Apr 2024: 0May 2024: 0Jun 2024: 0Jul 2024: 0Aug 2024: 0Sep 2024: 0Oct 2024: 0Nov 2024: 0Dec 2024: 02025Jan 2025: 0Feb 2025: 0Mar 2025: 0Apr 2025: 0May 2025: 0Jun 2025: 0Jul 2025: 0Aug 2025: 0Sep 2025: 0Oct 2025: 0Nov 2025: 0Dec 2025: 02026Jan 2026: 0Feb 2026: 0Mar 2026: 0Apr 2026: 0May 2026: 0Jun 2026: 0

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

0581152004: 1720042005: 272006: 3920062007: 532008: 4420082009: 382010: 3620102011: 312012: 5520122013: 1152014: 8220142015: 562016: 5820162017: 762018: 4720182019: 542020: 4820202021: 17

Reactions recorded in the reports

share of Klacid reports recording the termall reports in the database

  1. Drug interactionan interaction between medicines9.5%85
  2. Dyspnoeashortness of breath6.2%55
  3. Pruritusitching5.9%53
  4. Rashskin rash5.4%48
  5. Erythemaskin redness4.7%42
  6. Nauseafeeling sick4.6%41
  7. Diarrhoealoose or frequent stools3.8%34
  8. Angioedemadeep swelling of skin or mucous membranes2.7%24
  9. Urticariahives2.7%24
  10. Vomitingbeing sick2.7%24
  11. Pyrexiafever2.6%23
  12. Drug ineffectivethe medicine did not work as expected2.2%20
  13. Astheniaweakness or lack of energy2%18
  14. Abdominal painstomach or belly pain1.8%16
  15. Headachehead pain1.8%16
  16. Dysgeusiaaltered taste1.7%15
  17. Tremorshaking1.7%15
  18. Confusional stateconfusion1.6%14
  19. Face oedemaswelling of the face1.6%14
  20. Fatiguetiredness1.5%13
  21. International normalised ratio increasedblood clotting slower than intended (raised INR)1.5%13
  22. Jaundiceyellowing of the skin or eyes1.5%13
  23. Rhabdomyolysismuscle breakdown1.5%13
  24. Abdominal pain upperupper stomach pain1.3%12
  25. Blistera blister1.3%12
  26. Chillschills or shivering1.3%12
  27. Drug level increaseda raised blood level of the medicine1.3%12
  28. Rash maculo-papulara rash of flat and raised spots1.3%12

Top 30 of 314 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

Death8.1%72
Life-threatening7.7%69
Hospitalisation (initial or prolonged)49.4%441
Disability3.7%33
Congenital anomaly0.2%2
Other serious52.5%469
Not serious0.8%7

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 21.2%11
2 to 114.9%44
12 to 171.9%17
18 to 4420.9%187
45 to 6423.7%212
65 to 749.4%84
75 and over13.9%124
Age not given24%214

Patient sex

Female53.3%476
Male40.5%362
Not given6.2%55

Who reported

Physician42.8%382
Pharmacist8.4%75
Other health professional17.7%158
Lawyer0.1%1
Consumer or non-health professional24.5%219
Not given6.5%58

Age and sex as stated in the report; the reporter's qualification is the primary source recorded by FDA. 0.4% of reports give the United States as the country of the event or reporter.

Reason for use recorded

Indication as recorded (MedDRA)ReportsShare
Pneumonia667.4%
Helicobacter infection525.8%
Bronchitis394.4%
Respiratory tract infection202.2%
Bronchopneumonia161.8%
Infection121.3%

The indication field is filled in by the reporter and is often blank; shares are of all 893 reports.

In context

MeasureKlacidAll reports
Reports as suspect product89320,646,523
Share of that pool—0%
Reports, latest 12 months01,332,454
Marked serious99.2%57.4%
Death recorded among outcomes, per 1,000 reports8191
Hospitalisation recorded, per 1,000 reports494213
Consumer-filed share24.5%45.8%
Top term, share of reportsDrug interaction 9.5%0.8%

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 Klacid reports

How many adverse event reports has FDA received for Klacid?

893 reports list Klacid as a suspect or interacting product in the openFDA FAERS release of 28 Sep 2026, covering reports received through June 2026. 0 of them arrived in the latest 12 months. Another 337 list it only as a concomitant medication.

What reactions are recorded in Klacid reports?

drug interaction (9.5%), dyspnoea (6.2%), pruritus (5.9%), rash (5.4%) and erythema (4.7%). 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 Klacid was responsible.

How serious are the reports?

99.2% are marked serious by the reporter. Among the outcomes recorded, 8.1% of reports include death and 49.4% 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 (42.8%), consumer or non-health professional (24.5%) and other health professional (17.7%). Most reports reach FDA through the manufacturer, which must forward reports it receives.

Are reports for Klacid rising?

0 reports in the 12 months to June 2026, and none 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 Klacid 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 Klacid?

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 Klacid as a suspect or interacting product; reports listing it only as a concomitant medication (337) 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.