OpenClaim

Tecovirimat Side Effects

The most commonly reported side effects of tecovirimat include off label use, monkeypox, and nausea, based on 259 FDA adverse event reports from 2019 to 2025. 7.7% of reports found the drug to be ineffective.

Tecovirimat side effects

Percentages show how often each reaction appears relative to total reports for tecovirimat.

1
Off Label Use27.4%71
2
Monkeypox11.2%29
3
Nausea7.7%20
4
Drug Ineffective7.7%20
5
Drug Resistance7.3%19
6
Immune Reconstitution Inflammatory Syndrome6.2%16
7
Acute Kidney Injury5.8%15
8
Headache5.8%15
9
Fatigue5.4%14
10
Disease Progression5.0%13
11
Diarrhoea4.6%12
12
Drug Interaction3.9%10
13
Alanine Aminotransferase Increased3.9%10
14
Condition Aggravated3.9%10
15
Pancytopenia3.5%9

These are voluntary reports and do not establish that tecovirimat caused these reactions.

Report severity

53.3%Serious138 reports
29.3%Hospitalizations76 reports
12.4%Fatal32 reports

Seriousness is determined by the reporter, not by OpenClaim.

Tecovirimat drug interactions

Other drugs that appear in adverse event reports alongside tecovirimat. Drugs flagged as a suspected cause appear in the first column. Drugs taken at the same time but not suspected appear in the second.

Also suspected

1
Brincidofovir8.9%23
2
Vancomycin6.9%18
3
Prednisone6.2%16
4
Ganciclovir5.0%13
5
Cidofovir4.2%11
6
Mycophenolate4.2%11
7
Emtricitabine3.9%10
8
Tenofovir3.9%10
9
Methylprednisolone3.9%10
10
Tacrolimus3.5%9
11
Fluconazole3.5%9
12
Cefepime-hydrochloride3.1%8
13
Ceftriaxone-sodium2.7%7
14
Metronidazole1.9%5
15
Bictegravir1.9%5

Taken alongside

1
Cidofovir14.7%38
2
Tenofovir12.4%32
3
Emtricitabine10.8%28
4
Bictegravir8.9%23
5
Ceftriaxone-sodium8.5%22
6
Acyclovir7.3%19
7
Vancomycin5.8%15
8
Brincidofovir5.4%14
9
Acetaminophen4.6%12
10
Doxycycline4.6%12
11
Trifluridine3.9%10
12
Metronidazole3.9%10
13
Meropenem3.1%8
14
Amoxicillin2.7%7
15
Prednisone2.7%7

Co-occurrence in adverse event reports does not establish a drug interaction. Patients often take multiple medications, and these lists reflect prescribing patterns rather than causal relationships. Consult a healthcare provider about potential drug interactions.

Who reports tecovirimat side effects

5.0% of tecovirimat adverse event reports involve female patients and 74.9% involve male patients. The largest age group is adult at 97%. These figures reflect who reports side effects, not underlying risk.

Sex

Female5.0%
Male74.9%
Unknown20.1%

Age group

< 21.9%
2–110.0%
12–170.0%
18–6496.6%
65+1.4%

What is tecovirimat used for

Conditions and purposes for which patients were taking tecovirimat when the adverse event was reported.

Acquired Immunodeficiency SyndromeCow PoxCondition AggravatedCow PoxDisease ProgressionEvidence Based TreatmentHiv InfectionHerpes Virus InfectionImmunisationMonkeypoxOrthopoxvirus Test PositiveOral DisorderOrthopox Virus InfectionOrthopoxvirus Test PositiveProctitis

Showing 15 of 22 indications

Tecovirimat brand names and reporting trend

Tecovirimat is sold under the brand name Tpoxx.

Brand names

Tpoxx250

Quarterly reports (20192025)

202020242025

An upward trend reflects increased FAERS reporting overall, not necessarily increased risk.

Taking tecovirimat with another medication?

Ask OpenClaim about your specific drug combination. Get a sourced report using FDA data, drug labels, and medical literature.