Reported Reactions

Drugs

Product name as reported

Nelfinavir: adverse event reports filed with FDA

1,101 reports list it as a suspect or interacting product, 2004–2026.

1,101
reports as suspect product
0% of all reports · about 49 a year
13
reports, 12 months to June 2026
19 in the 12 months before
96.3%
marked serious by the reporter
57.4% across all reports
9.9%
record death among outcomes, as reported
109 reports · not verified by FDA

Between January 2004 and May 2026, 1,101 adverse event reports received by FDA list the product name "Nelfinavir" as reporters wrote it as a suspect or interacting product. Reports that mention it only as a concomitant medication (254) are left out of every figure here.

In the 12 months to June 2026, 13 reports listed it, down 32% from 19 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 49 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 resistance (12.4%), viral mutation identified (10.3%) and foetal exposure during pregnancy (9.5%). A report can list several reactions, so shares add to more than 100%; 415 different terms appear across these reports. Drug resistance is recorded in 12.4% of these reports, against 0.1% of all reports in the database.

96.3% of the reports are marked serious by the reporter; 9.9% record death among the outcomes and 15.2% record hospitalisation, as reported. 57.1% of the reports came from other health professionals, and the largest patient age group is 18 to 44 (22%). 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

01121Jul 2021: 2Aug 2021: 4Sep 2021: 2Oct 2021: 1Nov 2021: 11Dec 2021: 62022Jan 2022: 1Feb 2022: 6Mar 2022: 5Apr 2022: 3May 2022: 12Jun 2022: 3Jul 2022: 5Aug 2022: 3Sep 2022: 3Oct 2022: 3Nov 2022: 2Dec 2022: 32023Jan 2023: 1Feb 2023: 4Mar 2023: 6Apr 2023: 3May 2023: 7Jun 2023: 21Jul 2023: 2Aug 2023: 0Sep 2023: 0Oct 2023: 0Nov 2023: 0Dec 2023: 12024Jan 2024: 1Feb 2024: 0Mar 2024: 0Apr 2024: 0May 2024: 2Jun 2024: 0Jul 2024: 0Aug 2024: 5Sep 2024: 0Oct 2024: 0Nov 2024: 0Dec 2024: 02025Jan 2025: 5Feb 2025: 0Mar 2025: 1Apr 2025: 2May 2025: 0Jun 2025: 6Jul 2025: 3Aug 2025: 0Sep 2025: 1Oct 2025: 0Nov 2025: 1Dec 2025: 12026Jan 2026: 0Feb 2026: 4Mar 2026: 1Apr 2026: 0May 2026: 2Jun 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

0641272004: 3920042005: 722006: 732007: 7020072008: 642009: 712010: 3520102011: 142012: 172013: 1620132014: 482015: 832016: 12720162017: 422018: 722019: 3720192020: 532021: 382022: 4920222023: 452024: 82025: 2020252026: 7

2026 covers reports received through June 2026 only.

Reactions recorded in the reports

share of Nelfinavir reports recording the termall reports in the database

  1. Viral mutation identified10.3%113
  2. Foetal exposure during pregnancythe unborn baby was exposed to the medicine9.5%105
  3. Lipodystrophy acquiredchanges in body fat distribution7.9%87
  4. Drug ineffectivethe medicine did not work as expected7%77
  5. Treatment failurethe treatment did not work5.9%65
  6. Drug exposure during pregnancythe medicine was taken during pregnancy5.7%63
  7. Treatment noncompliancethe treatment was not taken as directed4%44
  8. Mitochondrial toxicity3.7%41
  9. Diplopiadouble vision3.5%38
  10. Progressive external ophthalmoplegia3.1%34
  11. Diarrhoealoose or frequent stools2.6%29
  12. Portal hypertension2.5%28
  13. Pregnancypregnancy2.3%25
  14. Myocardial infarctionheart attack2%22
  15. Immune reconstitution syndrome1.9%21
  16. Nauseafeeling sick1.9%21
  17. Exposure during pregnancythe medicine was taken during pregnancy1.8%20
  18. Drug interactionan interaction between medicines1.7%19
  19. Premature babya baby born early1.7%19
  20. Hyperlipidaemiaraised blood fats1.6%18
  21. Hypospadias1.6%18
  22. HIV infectionHIV infection1.5%17
  23. Anaemialow red blood cells1.5%16
  24. Gynaecomastiabreast enlargement in men1.5%16

Top 30 of 415 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

Death9.9%109
Life-threatening3%33
Hospitalisation (initial or prolonged)15.2%167
Disability1.5%17
Congenital anomaly10.7%118
Other serious75.7%833
Not serious3.7%41

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 23.1%34
2 to 113.7%41
12 to 171.8%20
18 to 4422%242
45 to 6419.1%210
65 to 740.7%8
75 and over1.3%14
Age not given48.3%532

Patient sex

Female25.2%277
Male40.1%442
Not given34.7%382

Who reported

Physician18.9%208
Pharmacist0.4%4
Other health professional57.1%629
Lawyer0%0
Consumer or non-health professional9.7%107
Not given13.9%153

Age and sex as stated in the report; the reporter's qualification is the primary source recorded by FDA. 27.6% of reports give the United States as the country of the event or reporter.

Reason for use recorded

Indication as recorded (MedDRA)ReportsShare
Hiv infection70664.1%
Antiretroviral therapy696.3%
Drug exposure during pregnancy131.2%
Antiviral prophylaxis111%
Pancreatic carcinoma100.9%
Acquired immunodeficiency syndrome80.7%

The indication field is filled in by the reporter and is often blank; shares are of all 1,101 reports.

In context

MeasureNelfinavirAll reports
Reports as suspect product1,10120,646,523
Share of that pool—0%
Reports, latest 12 months131,332,454
Marked serious96.3%57.4%
Death recorded among outcomes, per 1,000 reports9991
Hospitalisation recorded, per 1,000 reports152213
Consumer-filed share9.7%45.8%
Top term, share of reportsDrug resistance 12.4%0.1%

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 Nelfinavir reports

How many adverse event reports has FDA received for Nelfinavir?

1,101 reports list Nelfinavir as a suspect or interacting product in the openFDA FAERS release of 28 Sep 2026, covering reports received through June 2026. 13 of them arrived in the latest 12 months. Another 254 list it only as a concomitant medication.

What reactions are recorded in Nelfinavir reports?

drug resistance (12.4%), viral mutation identified (10.3%), foetal exposure during pregnancy (9.5%), virologic failure (9.4%) and lipodystrophy acquired (7.9%). 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 Nelfinavir was responsible.

How serious are the reports?

96.3% are marked serious by the reporter. Among the outcomes recorded, 9.9% of reports include death and 15.2% 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?

other health professional (57.1%), physician (18.9%) and not given (13.9%). Most reports reach FDA through the manufacturer, which must forward reports it receives.

Are reports for Nelfinavir rising?

13 reports in the 12 months to June 2026, down 32% from 19 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 Nelfinavir 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 Nelfinavir?

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 Nelfinavir as a suspect or interacting product; reports listing it only as a concomitant medication (254) 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.