Acyclovir: Price, Dosage & Where to Buy

Acyclovir is an antiviral medicine used against infections caused by herpes viruses. It is most commonly prescribed for shingles, genital herpes, or chickenpox, depending on the formulation and clinical situation. Acyclovir has been available as a generic medicine since 1997-04-22 and requires a prescription in the United Kingdom.

Acyclovir is an antiviral medicine that interferes with the ability of herpes viruses to copy their genetic material. After entering infected cells, it is converted into an active form by processes that are more prominent in virus-infected cells. The active medicine then blocks a viral enzyme needed to build new viral DNA.

This limits the production of new virus and can help shorten or control an episode. Acyclovir does not eradicate herpes viruses from the body, so infections can recur. Its effect is directed at viral replication rather than directly treating every symptom caused by the infection.

Acyclovir tablets are indicated for the acute treatment of herpes zoster, commonly called shingles. They are also indicated for initial episodes and management of recurrent episodes of genital herpes. Acyclovir tablets can be used to treat chickenpox, also called varicella.

Intravenous acyclovir is indicated for varicella-zoster infections in people who are immunocompromised. The medicine works against herpes viruses, but it does not remove the virus from the body. A clinician decides which formulation is appropriate for the infection and the person’s circumstances.

The label lists oral capsules of 200 mg, oral suspension of 200 mg/5 mL, and oral tablets of 400 mg and 800 mg. The label lists topical creams, ointments, and ophthalmic ointment at 50 mg/g or 30 mg/g, plus intravenous forms of 1 g, 500 mg, 50 mg/mL, 500 mg/10 mL, and 1000 mg/20 mL. The usual starting dose is 800 mg every 4 hours orally, 5 times daily for 7 to 10 days for acute shingles.

The usual starting dose is 200 mg every 4 hours, 5 times daily for 10 days for initial genital herpes. The label lists 400 mg 2 times daily for up to 12 months for chronic suppressive therapy.

The usual starting dose is 800 mg 4 times daily for 5 days for adults and children over 40 kg with chickenpox. Renal impairment requires modification of the regimen, and haemodialysis may require an additional dose after each dialysis.

Store the tablets at 20° to 25°C and protect them from light and moisture, as directed on the label. Keep the medicine in its original packaging and out of the reach of children to maintain quality.

A missed dose can reduce the regular antiviral coverage intended by the prescribed regimen. General pharmacy advice is to take the missed dose when remembered unless it is nearly time for the next scheduled dose, in which case it is usually omitted.

A double dose should not be used to make up for a missed dose. Advice may need to be individualised when renal impairment or dialysis is involved, so a pharmacist or doctor can clarify the schedule.

The label does not specify pregnancy data for acyclovir. Anyone who is pregnant, planning a pregnancy, or breastfeeding should discuss acyclovir with a doctor or pharmacist before treatment. This discussion can consider the infection, the formulation, and any other medicines being used.