Acyclovir is a deoxyguanosine analog drug that requires a virus-specific enzyme to convert to the active metabolite.
Resistance to acyclovir develops in HSV or VZV through
viral thymidine kinase or DNA polymerase alterations.
Precaution.
- Maintain adequate hydration.
- Allergy to acyclovir.
- Renal impairment
- Elderly
Mechanism of action.
- The drug functions by inhibiting DNA synthesis and viral replication in the body.
Adverse effects
- Topical application: Stinging and burning sensation experienced after each application.
- Oral application; headache, nausea, and body weakness.
- Intravenous application: Rashes, sweating, emesis, and blood pressure falls.
- A decrease in the glomerular filtration rate occurs in those with kidney disease.
- Reversible neurologic reactions include; tremors, lethargy, hallucinations, disorientation, convulsions, and coma.
Drug interactions.
- Probenecid and cimetidine inhibit renal clearance of the drug.
- Nephrotoxic drugs enhance nephrotoxicity.
Dosage.
- ZOVIRAX 200 mg tablet, 250 mg/vial for intravenous injection.
- ACYCLOVIR 200 mg tablet, 5% skin cream; HERPES 200 mg tablet, 3% eye ointment.