Reported Reactions

Drugs

Brand name · Pyrimethamine

Daraprim: adverse event reports filed with FDA

513 reports list it as a suspect or interacting product, 2004–2026.

513
reports as suspect product
0% of all reports · about 23 a year
4
reports, 12 months to June 2026
13 in the 12 months before
49.5%
marked serious by the reporter
57.4% across all reports
10.7%
record death among outcomes, as reported
55 reports · not verified by FDA

Between April 2004 and March 2026, 513 adverse event reports received by FDA list the brand name Daraprim (pyrimethamine) as a suspect or interacting product. Reports that mention it only as a concomitant medication (81) are left out of every figure here.

In the 12 months to June 2026, 4 reports listed it, down 69% from 13 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 23 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.

The reactions recorded most often are nausea (17.9%), off label use (17.7%) and vomiting (11.5%). A report can list several reactions, so shares add to more than 100%; 172 different terms appear across these reports. Nausea is recorded in 17.9% of these reports, against 3.8% of all reports in the database.

49.5% of the reports are marked serious by the reporter; 10.7% record death among the outcomes and 26.3% record hospitalisation, as reported. 43.5% of the reports came from consumers, and the largest patient age group is 45 to 64 (28.5%). 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

01428Jul 2021: 1Aug 2021: 3Sep 2021: 3Oct 2021: 3Nov 2021: 0Dec 2021: 02022Jan 2022: 2Feb 2022: 28Mar 2022: 2Apr 2022: 3May 2022: 2Jun 2022: 0Jul 2022: 0Aug 2022: 0Sep 2022: 1Oct 2022: 1Nov 2022: 0Dec 2022: 02023Jan 2023: 2Feb 2023: 0Mar 2023: 12Apr 2023: 3May 2023: 1Jun 2023: 1Jul 2023: 1Aug 2023: 1Sep 2023: 0Oct 2023: 2Nov 2023: 1Dec 2023: 12024Jan 2024: 0Feb 2024: 0Mar 2024: 10Apr 2024: 0May 2024: 1Jun 2024: 2Jul 2024: 1Aug 2024: 0Sep 2024: 0Oct 2024: 0Nov 2024: 1Dec 2024: 02025Jan 2025: 0Feb 2025: 1Mar 2025: 9Apr 2025: 0May 2025: 0Jun 2025: 1Jul 2025: 0Aug 2025: 0Sep 2025: 0Oct 2025: 0Nov 2025: 0Dec 2025: 12026Jan 2026: 0Feb 2026: 0Mar 2026: 3Apr 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

040802004: 720042005: 42006: 52007: 620072008: 132009: 62010: 920102011: 132012: 72014: 220142015: 82016: 352017: 6120172018: 662019: 512020: 8020202021: 462022: 392023: 2520232024: 152025: 122026: 32026

2026 covers reports received through June 2026 only.

Reactions recorded in the reports

share of Daraprim reports recording the termall reports in the database

  1. Nauseafeeling sick17.9%92
  2. Off label useused for a purpose or in a way not on the label17.7%91
  3. Vomitingbeing sick11.5%59
  4. Rashskin rash7.4%38
  5. Headachehead pain7.2%37
  6. Deaththe patient died; cause not stated by this term6%31
  7. Dizzinesslight-headedness or unsteadiness5.7%29
  8. Decreased appetitereduced appetite4.3%22
  9. Insomniadifficulty sleeping4.1%21
  10. Fatiguetiredness3.3%17
  11. Astheniaweakness or lack of energy3.1%16
  12. Dyspnoeashortness of breath3.1%16
  13. Hospitalisationadmission to hospital3.1%16
  14. Neutropenialow neutrophils, a type of white blood cell2.9%15
  15. Pyrexiafever2.9%15
  16. Seizurea fit or convulsion2.5%13
  17. Acute kidney injurysudden loss of kidney function2.1%11
  18. Dehydrationdehydration2.1%11
  19. Pruritusitching2.1%11
  20. Tremorshaking2.1%11
  21. Malaisegeneral feeling of being unwell1.8%9
  22. Diarrhoealoose or frequent stools1.6%8
  23. Abdominal discomfortstomach discomfort1.4%7
  24. Abdominal pain upperupper stomach pain1.4%7
  25. Anxietyanxiety1.4%7
  26. Hypersensitivityan allergic-type reaction1.4%7
  27. Pancytopenialow counts of all blood cells1.4%7
  28. Myalgiamuscle pain1.2%6
  29. Weight decreasedweight loss1.2%6

Top 30 of 172 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

Death10.7%55
Life-threatening1.6%8
Hospitalisation (initial or prolonged)26.3%135
Disability0.6%3
Congenital anomaly0.4%2
Other serious24.4%125
Not serious50.5%259

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 21.8%9
2 to 111.9%10
12 to 171.4%7
18 to 4426.9%138
45 to 6428.5%146
65 to 746.6%34
75 and over3.3%17
Age not given29.6%152

Patient sex

Female47.2%242
Male50.3%258
Not given2.5%13

Who reported

Physician11.1%57
Pharmacist31%159
Other health professional12.5%64
Lawyer0%0
Consumer or non-health professional43.5%223
Not given1.9%10

Age and sex as stated in the report; the reporter's qualification is the primary source recorded by FDA. 84.8% of reports give the United States as the country of the event or reporter.

Reason for use recorded

Indication as recorded (MedDRA)ReportsShare
Toxoplasmosis21141.1%
Eye infection toxoplasmal448.6%
Cerebral toxoplasmosis377.2%
Hiv infection214.1%
Gastrointestinal disorder30.6%
Congenital toxoplasmosis20.4%

The indication field is filled in by the reporter and is often blank; shares are of all 513 reports.

In context

MeasureDaraprimAll reports
Reports as suspect product51320,646,523
Share of that pool—0%
Reports, latest 12 months41,332,454
Marked serious49.5%57.4%
Death recorded among outcomes, per 1,000 reports10791
Hospitalisation recorded, per 1,000 reports263213
Consumer-filed share43.5%45.8%
Top term, share of reportsNausea 17.9%3.8%

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 Daraprim reports

How many adverse event reports has FDA received for Daraprim?

513 reports list Daraprim as a suspect or interacting product in the openFDA FAERS release of 28 Sep 2026, covering reports received through June 2026. 4 of them arrived in the latest 12 months. Another 81 list it only as a concomitant medication.

What reactions are recorded in Daraprim reports?

nausea (17.9%), off label use (17.7%), vomiting (11.5%), rash (7.4%) and headache (7.2%). 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 Daraprim was responsible.

How serious are the reports?

49.5% are marked serious by the reporter. Among the outcomes recorded, 10.7% of reports include death and 26.3% 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 (43.5%), pharmacist (31%) and other health professional (12.5%). Most reports reach FDA through the manufacturer, which must forward reports it receives.

Are reports for Daraprim rising?

4 reports in the 12 months to June 2026, down 69% from 13 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 Daraprim 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 Daraprim?

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 Daraprim as a suspect or interacting product; reports listing it only as a concomitant medication (81) 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.