Entecavir Side Effects

Medically reviewed by Drugs.com. Last updated on Jan 22, 2024.

Applies to entecavir: oral solution, oral tablet.

Serious side effects of Entecavir

Along with its needed effects, entecavir may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur while taking entecavir:

Incidence not known

• Abdominal or stomach discomfort
• cough
• decreased appetite
• diarrhea
• difficulty with swallowing
• dizziness
• fast heartbeat
• fast, shallow breathing
• general feeling of discomfort
• hives, itching, or rash
• muscle pain or cramping
• nausea
• puffiness or swelling of the eyelids or around the eyes, face, lips, or tongue
• right upper abdominal or stomach pain and fullness
• sleepiness
• tightness in the chest
• unusual tiredness or weakness

Other side effects of Entecavir

Some side effects of entecavir may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects.

Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

Less common

• Acid or sour stomach
• belching
• headache
• heartburn
• indigestion
• stomach discomfort, upset, or pain

Rare

• Trouble sleeping
• Unusual drowsiness

Incidence not known

• Hair loss
• thinning of the hair

For Healthcare Professionals

Applies to entecavir: oral solution, oral tablet.

General

The most common side effects reported in patients with chronic hepatitis B virus (HBV) infection and compensated liver disease during clinical trials have included headache, fatigue, dizziness, and nausea. One percent of patients discontinued therapy due to side effects or laboratory abnormalities (compared to 4% of lamivudine-treated patients).

The most common side effects reported in patients with chronic HBV infection and evidence of hepatic decompensation (n=102) through Week 48 of a study have included peripheral edema, ascites, pyrexia, hepatic encephalopathy, and upper respiratory infection. The cumulative death rate was 23% with entecavir during the first 48 weeks of therapy (compared to 33% with adefovir). The majority of deaths were due to liver-related causes such as hepatic failure, hepatic encephalopathy, hepatorenal syndrome, and upper gastrointestinal hemorrhage. Through Week 48, up to 7% of patients discontinued this drug due to a side effect.^[Ref]

Hepatic

Elevated ALT (greater than 10 times ULN and greater than 2 times baseline: up to 2%; greater than 5 times ULN: up to 12%; greater than 3 times baseline: up to 5%; greater than 2 times baseline [with total bilirubin greater than 2 times ULN and greater than 2 times baseline]: up to 1%) and total bilirubin (greater than 2.5 times ULN; up to 3%) have been reported.

Posttreatment exacerbations of hepatitis or ALT flare, as defined by ALT greater than 10 times ULN and greater than 2 times baseline, have been reported in patients who discontinued therapy at or after 52 weeks after achieving a defined treatment response (nucleoside-naive hepatitis B e antigen [HBeAg]-positive: 2%; nucleoside-naive HBeAg-negative: 8%; lamivudine-refractory: 12%). The median time to exacerbation was 23 to 24 weeks. The rate may be higher in patients who discontinue this drug without regard to treatment response.

Hepatic encephalopathy and deaths due to liver-related causes (such as hepatic failure, hepatic encephalopathy, hepatorenal syndrome, and upper gastrointestinal hemorrhage) were reported in patients with hepatic decompensation.^[Ref]

Very common (10% or more): Elevated ALT (up to 12%), posttreatment exacerbation of hepatitis/ALT flare (up to 12%), deaths due to liver-related causes (e.g., hepatic failure, hepatic encephalopathy, hepatorenal syndrome, upper gastrointestinal hemorrhage; 11%), hepatic encephalopathy (10%)

Common (1% to 10%): On-treatment exacerbation of hepatitis/ALT flares

Frequency not reported: Elevated AST, lactic acidosis and severe hepatomegaly with steatosis (including fatal cases), severe acute exacerbations of hepatitis B (after discontinuation of therapy)

Postmarketing reports: Increased transaminases^[Ref]

Hematologic

Very common (10% or more): Decreased albumin (up to 30%), decreased platelets (up to 20%)

Frequency not reported: Neutropenia^[Ref]

Decreased albumin (less than 2.5 g/dL) and platelets (less than 50,000/mm3) were reported in 30% and 20% of patients with hepatic decompensation, respectively.

Neutropenia was very common in pediatric patients.^[Ref]

Gastrointestinal

Very common (10% or more): Elevated lipase (up to 18%)

Common (1% to 10%): Diarrhea, dyspepsia, nausea, vomiting, elevated amylase

Frequency not reported: Abdominal pain (unspecified), upper abdominal pain, upper gastrointestinal hemorrhage^[Ref]

Elevated lipase (greater than 3 times baseline: up to 18%; at least 2.1 times upper limit of normal [ULN]: 7%) and amylase (greater than 3 times baseline: 2%) have been reported.^[Ref]

Other

Peripheral edema, ascites, and pyrexia were reported in patients with hepatic decompensation.^[Ref]

Very common (10% or more): Peripheral edema (16%), ascites (15%), pyrexia/fever (14%)

Common (1% to 10%): Fatigue

Frequency not reported: Accidental injury, influenza^[Ref]

Oncologic

Hepatocellular carcinoma was reported in patients with hepatic decompensation.

Malignant neoplasms, occurring at a rate of 8.4 per 1000 patient-years, have been reported.^[Ref]

Very common (10% or more): Hepatocellular carcinoma (up to 12%)

Frequency not reported: Malignant neoplasms^[Ref]

Renal

Confirmed creatinine increase of at least 0.5 mg/dL was reported in up to 2% of patients with compensated liver disease. Confirmed increase in serum creatinine of 0.5 mg/dL (11%) and renal failure were reported in patients with hepatic decompensation.^[Ref]

Very common (10% or more): Increased serum creatinine (up to 11%)

Uncommon (0.1% to 1%): Renal failure^[Ref]

Respiratory

Upper respiratory infection was reported in patients with hepatic decompensation.^[Ref]

Very common (10% or more): Upper respiratory infection (10%)

Frequency not reported: Cough, nasopharyngitis, rhinitis^[Ref]

Metabolic

Common (1% to 10%): Elevated fasting hyperglycemia, decreased blood bicarbonate

Frequency not reported: Elevated alkaline phosphatase

Postmarketing reports: Lactic acidosis^[Ref]

Elevated fasting hyperglycemia (greater than 250 mg/dL) was reported in up to 3% of patients.

Decreased blood bicarbonate was reported in patients with hepatic decompensation.

Lactic acidosis was often associated with hepatic decompensation, other serious medical conditions, or drug exposures.^[Ref]

Genitourinary

Common (1% to 10%): Hematuria, glycosuria

Frequency not reported: Dysuria^[Ref]

Grade 3 to 4 hematuria (9%) and glycosuria (4%) were reported.^[Ref]

Nervous system

Common (1% to 10%): Headache, dizziness, somnolence^[Ref]

Psychiatric

Common (1% to 10%): Insomnia^[Ref]

Hypersensitivity

Postmarketing reports: Anaphylactoid reaction^[Ref]

Dermatologic

Frequency not reported: Erythema, photosensitivity with lethargy

Postmarketing reports: Rash, alopecia^[Ref]

Musculoskeletal

Frequency not reported: Arthralgia, myalgia, back pain^[Ref]

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Some side effects may not be reported. You may report them to the FDA.

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