OpenClaim

Entecavir Side Effects

The most commonly reported side effects of entecavir include off label use, death, and drug resistance, based on 12,107 FDA adverse event reports from 2004 to 2025. 3.4% of reports found the drug to be ineffective.

Entecavir side effects

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

1
Off Label Use4.3%523
2
Death4.3%522
3
Drug Ineffective3.4%416
4
Drug Resistance3.0%365
5
Diarrhoea2.9%350
6
Fatigue2.8%336
7
Pyrexia2.6%311
8
Hepatitis B2.5%308
9
Nausea2.4%293
10
Pneumonia2.4%289
11
Platelet Count Decreased2.3%274
12
Anaemia1.9%226
13
Hepatocellular Carcinoma1.8%221
14
Renal Impairment1.8%219
15
Asthenia1.8%214

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

Report severity

85.7%Serious10,375 reports
37.3%Hospitalizations4,519 reports
16.5%Fatal1,998 reports

Seriousness is determined by the reporter, not by OpenClaim.

Entecavir drug interactions

Other drugs that appear in adverse event reports alongside entecavir. 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
Tenofovir7.2%877
2
Rituximab5.4%654
3
Adefovir-dipivoxil5.3%640
4
Lenalidomide4.3%524
5
Lamivudine3.8%463
6
Cyclophosphamide3.7%448
7
Tacrolimus3.3%399
8
Prednisone2.9%348
9
Dexamethasone2.7%332
10
Doxorubicin-hydrochloride2.6%314
11
Mycophenolate2.4%291
12
Lenvatinib-mesylate2.3%278
13
Bevacizumab2.0%247
14
Sorafenib-tosylate2.0%246
15
Atezolizumab2.0%246

Taken alongside

1
Acyclovir7.6%924
2
Acetaminophen6.8%822
3
Amlodipine6.1%738
4
Furosemide5.6%684
5
Pantoprazole-sodium5.6%673
6
Aspirin5.3%647
7
Dexamethasone5.0%600
8
Omeprazole4.9%599
9
Prednisone4.5%544
10
Sulfamethoxazole4.3%524
11
Allopurinol3.8%461
12
Ondansetron3.7%445
13
Atorvastatin-calcium3.5%428
14
Insulin3.4%417
15
Trimethoprim3.3%398

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 entecavir side effects

30.8% of entecavir adverse event reports involve female patients and 57.0% involve male patients. The largest age group is adult at 65%. These figures reflect who reports side effects, not underlying risk.

Sex

Female30.8%
Male57.0%
Unknown12.3%

Age group

< 20.5%
2–110.4%
12–170.3%
18–6464.8%
65+34.1%

What is entecavir used for

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

Abdominal Pain UpperAcute Hepatic FailureAcute Hepatitis BAcute Myeloid LeukaemiaAdult T-cell Lymphoma/leukaemiaAlanine Aminotransferase IncreasedAntibiotic ProphylaxisAntiretroviral TherapyAntiviral ProphylaxisAntiviral TreatmentAplastic AnaemiaArthritis BacterialAscitesAspartate Aminotransferase IncreasedAtrioventricular Block Complete

Showing 15 of 295 indications

Entecavir brand names and reporting trend

Entecavir is sold under the brand name Entecavir.

Brand names

Entecavir7,886

Quarterly reports (20042025)

20052010201520202025

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

Taking entecavir with another medication?

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