Cavir

Indications

Entecavir is used to treat long-term (chronic) hepatitis B virus infection in adults and children with active liver inflammation, including people with liver scarring (cirrhosis). It controls the virus but does not cure the infection, so treatment is usually long-term.

How It Works

Entecavir is an antiviral medicine (a nucleoside analogue). It blocks the enzyme the hepatitis B virus uses to copy itself, which lowers the amount of virus in the blood and gives the liver a chance to heal.

Dosage and Administration

Adults: usually 0.5 mg once a day. People whose virus is resistant to Lamivudine, or who have advanced liver disease, are usually given 1 mg once a day. The doctor will lower the dose or space the doses out for people with kidney problems. Children: dose by weight, as prescribed.

Take on an empty stomach, at least 2 hours after a meal and at least 2 hours before the next meal, at about the same time each day. Do not stop taking it unless the doctor tells you to.

Interactions

Entecavir has few interactions. Medicines that affect the kidneys, such as aminoglycoside antibiotics, Ciclosporin, Tacrolimus or regular high-dose NSAIDs, may change its levels, so the doctor may check kidney function. Tell the doctor about all other medicines, including herbal products.

Contraindications

Allergy to entecavir or any ingredient of the product.

Side Effects

Common: headache, tiredness, dizziness, nausea and trouble sleeping. Blood tests may show changes in liver enzymes.

Get urgent medical help for yellow skin or eyes, dark urine, pale stools, swelling of the belly, confusion or bleeding easily (signs of worsening liver disease), or for deep fast breathing, unusual muscle pain, severe tiredness, cold hands and feet, or stomach pain with nausea and vomiting (signs of lactic acidosis, a rare but serious side effect).

Pregnancy and Lactation

There is limited information on use in pregnancy. Tell the doctor if you are pregnant or planning a pregnancy; another hepatitis B medicine may be preferred. Babies of mothers with hepatitis B need the hepatitis B vaccine and immunoglobulin at birth. Breastfeeding is not recommended while taking entecavir.

Precautions and Warnings

• Stopping treatment can cause a severe flare of hepatitis; liver tests are needed for several months after stopping.
• An HIV test should be done before starting. In people with untreated HIV, entecavir alone can make HIV resistant to treatment.
• Entecavir does not stop hepatitis B from spreading to others. Use condoms, do not share razors, toothbrushes or needles, and make sure close contacts are vaccinated.
• Regular blood tests to check the virus, liver and kidneys are needed.

Overdose

There is little experience of overdose. Contact a doctor or go to hospital; the person will be watched and treated for any symptoms.

Therapeutic Class

Antiviral for hepatitis B (nucleoside analogue).

Storage

Store below 30°C in a dry place, away from light and out of the reach of children. Keep the oral solution in its carton; do not freeze.