Acyclovir therapy can rarely cause which kidney-related complication?

• A. Kidney injury
• B. Liver damage
• C. Heart attack
• D. Blindness

Answer: (A)

Acyclovir can cause nephrotoxicity through crystal precipitation in the renal tubules when given by IV, especially at high doses or if hydration is inadequate. The drug is cleared by the kidneys, and if it becomes concentrated in the tubules it can form crystals that obstruct flow and reduce kidney function, leading to acute kidney injury. This risk is higher with rapid infusion, dehydration, high-dose regimens, or preexisting kidney impairment, and it can often be mitigated by giving IV acyclovir with generous intravenous fluids and adjusting the dose based on renal function.

The other options don’t fit the kidney-focused adverse effect profile of acyclovir. Liver damage, heart attack, and blindness aren’t the typical kidney-related complication associated with this drug.