Adverse Effects of Acyclovir

By any route of administration, acyclovir is generally well tolerated. Gastrointestinal (GI) disturbances and headache can occur. Given IV, the drug may cause phlebitis and inflammation at sites of infusion or extravasation. IV acyclovir can also cause reversible renal dysfunction because of crystalline nephropathy; rapid infusion, dehydration,renal insufficiency and high dosage increase the risk. IV and rarely oral acyclovir have been associated with encephalopathy, conatining tremors, hallucinations, seizures and coma.