Reported Reactions

Drugs › Intestinal lipase inhibitor

Generic name

Orlistat: adverse event reports filed with FDA

1,456 reports list it as a suspect or interacting product, 2004–2026. Class: Intestinal lipase inhibitor. Also reported as Orlistat Capsule.

1,456
reports as suspect product
0% of all reports · about 65 a year
64
reports, 12 months to June 2026
68 in the 12 months before
95.2%
marked serious by the reporter
22.2% across the class
3.8%
record death among outcomes, as reported
56 reports · not verified by FDA

Between January 2004 and June 2026, 1,456 adverse event reports received by FDA list orlistat, a generic name as a suspect or interacting product. Reports that mention it only as a concomitant medication (713) are left out of every figure here.

In the 12 months to June 2026, 64 reports listed it, close to the 68 of 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 65 reports a year and 0% of the 20,646,523 reports in the database, and 6% of the reports for the intestinal lipase inhibitor class. How many people take it is not in the data, so a count is not a rate of occurrence.

The MedDRA terms listed most often are drug interaction (8%), diarrhoea (5.5%) and vomiting (3.7%). A report can list several reactions, so shares add to more than 100%; 367 different terms appear across these reports. Drug interaction is recorded in 8% of these reports, a larger share than in the median intestinal lipase inhibitor drug (3.5%).

95.2% of the reports are marked serious by the reporter (22.2% across the class); 3.8% record death among the outcomes and 40.9% record hospitalisation, as reported. 53.6% of the reports came from consumers, and the largest patient age group is 45 to 64 (27.8%). 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

0714Jul 2021: 14Aug 2021: 5Sep 2021: 14Oct 2021: 3Nov 2021: 1Dec 2021: 22022Jan 2022: 1Feb 2022: 1Mar 2022: 2Apr 2022: 0May 2022: 2Jun 2022: 0Jul 2022: 3Aug 2022: 4Sep 2022: 1Oct 2022: 0Nov 2022: 1Dec 2022: 22023Jan 2023: 2Feb 2023: 4Mar 2023: 0Apr 2023: 4May 2023: 2Jun 2023: 0Jul 2023: 5Aug 2023: 3Sep 2023: 3Oct 2023: 3Nov 2023: 5Dec 2023: 02024Jan 2024: 0Feb 2024: 0Mar 2024: 2Apr 2024: 3May 2024: 0Jun 2024: 6Jul 2024: 5Aug 2024: 5Sep 2024: 11Oct 2024: 4Nov 2024: 2Dec 2024: 32025Jan 2025: 6Feb 2025: 6Mar 2025: 7Apr 2025: 2May 2025: 7Jun 2025: 10Jul 2025: 8Aug 2025: 3Sep 2025: 0Oct 2025: 4Nov 2025: 5Dec 2025: 72026Jan 2026: 3Feb 2026: 5Mar 2026: 13Apr 2026: 9May 2026: 3Jun 2026: 4

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

01983952004: 1720042005: 212006: 122007: 10320072008: 3952009: 1612010: 4920102011: 242012: 442013: 4020132014: 392015: 472016: 3620162017: 332018: 982019: 5420192020: 462021: 462022: 1720222023: 312024: 412025: 6520252026: 37

2026 covers reports received through June 2026 only.

Reactions recorded in the reports

share of Orlistat reports recording the termmedian drug in intestinal lipase inhibitor

  1. Drug interactionan interaction between medicines8%116
  2. Diarrhoealoose or frequent stools5.5%80
  3. Vomitingbeing sick3.7%54
  4. Headachehead pain3.6%53
  5. Abdominal painstomach or belly pain3.4%50
  6. Fatiguetiredness3.4%49
  7. Cerebral venous thrombosis2.3%33
  8. Nauseafeeling sick2.2%32
  9. Acute kidney injurysudden loss of kidney function2.1%31
  10. Abortion spontaneousmiscarriage2.1%30
  11. Drug ineffectivethe medicine did not work as expected2.1%30
  12. Falla fall1.9%28
  13. Deaththe patient died; cause not stated by this term1.8%26
  14. Myocardial infarctionheart attack1.8%26
  15. Product use in unapproved indicationused for a purpose not on the label1.8%26
  16. Dizzinesslight-headedness or unsteadiness1.7%25
  17. Drug exposure during pregnancythe medicine was taken during pregnancy1.6%24
  18. Dyspnoeashortness of breath1.6%24
  19. Renal impairmentreduced kidney function1.6%24
  20. Drug abusemisuse of a medicine1.5%22
  21. Malaisegeneral feeling of being unwell1.5%22
  22. Weight increasedweight gain1.5%22
  23. Thalamic infarction1.4%21
  24. Abdominal pain upperupper stomach pain1.4%20
  25. Chest painchest pain1.4%20
  26. Breast cancerbreast cancer1.3%19

Top 30 of 367 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 3 drugs in the intestinal lipase inhibitor 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

Death3.8%56
Life-threatening6.5%95
Hospitalisation (initial or prolonged)40.9%596
Disability4.7%68
Congenital anomaly2.1%31
Other serious57.8%842
Not serious4.8%70

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 24,403 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 20.1%2
2 to 110.5%7
12 to 171%15
18 to 4418.9%275
45 to 6427.8%405
65 to 747.3%107
75 and over1.3%19
Age not given43%626

Patient sex

Female68.4%996
Male21.3%310
Not given10.3%150

Who reported

Physician16.5%240
Pharmacist5.4%78
Other health professional20.9%305
Lawyer0.2%3
Consumer or non-health professional53.6%780
Not given3.4%50

Age and sex as stated in the report; the reporter's qualification is the primary source recorded by FDA. 9% of reports give the United States as the country of the event or reporter.

Reason for use recorded

Indication as recorded (MedDRA)ReportsShare
Obesity73250.3%
Weight decreased15510.6%
Weight control402.7%
Overweight251.7%
Abnormal weight gain141%
Weight loss diet80.5%

The indication field is filled in by the reporter and is often blank; shares are of all 1,456 reports.

In context

MeasureOrlistatIntestinal lipase inhibitorAll reports
Reports as suspect product1,45624,40320,646,523
Share of that pool—6%0%
Reports, latest 12 months64—1,332,454
Marked serious95.2%22.2%57.4%
Death recorded among outcomes, per 1,000 reports38691
Hospitalisation recorded, per 1,000 reports40968213
Consumer-filed share53.6%92%45.8%
Top term, share of reportsDrug interaction 8%median 3.5%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."

Other drugs in the intestinal lipase inhibitor class

DrugName typeReportsLatest 12 monthsMarked serious
Allibrand21,22413912.1%
Xenicalbrand1,723284.8%

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 Orlistat reports

How many adverse event reports has FDA received for Orlistat?

1,456 reports list Orlistat as a suspect or interacting product in the openFDA FAERS release of 28 Sep 2026, covering reports received through June 2026. 64 of them arrived in the latest 12 months. Another 713 list it only as a concomitant medication.

What reactions are recorded in Orlistat reports?

drug interaction (8%), diarrhoea (5.5%), vomiting (3.7%), headache (3.6%) and abdominal pain (3.4%). 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 Orlistat was responsible.

How serious are the reports?

95.2% are marked serious by the reporter. Among the outcomes recorded, 3.8% of reports include death and 40.9% 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 (53.6%), other health professional (20.9%) and physician (16.5%). Most reports reach FDA through the manufacturer, which must forward reports it receives.

Are reports for Orlistat rising?

64 reports in the 12 months to June 2026, close to the 68 of 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 Orlistat 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 Orlistat?

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 Orlistat as a suspect or interacting product; reports listing it only as a concomitant medication (713) 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.