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Short answer How long Acyclovir Topical stays in your system Common questions Related questions Sources**Topical acyclovir barely enters your bloodstream, and the small amount that does is cleared within about a day of your last application.**
Acyclovir cream and ointment are designed to act in the skin, so measured blood levels after topical use are low or undetectable. Any absorbed drug leaves through your kidneys, with a blood half-life of roughly 2 to 3 hours in adults with normal kidney function, which means about 12 to 15 hours to clear nearly all of it. Reduced kidney function slows that clearance, though the amounts involved with skin use remain very small. The medicine you apply stays on the surface until it soaks in or washes off, usually within a few hours. Wash your hands before and after each application, and finish the full course even if the sore starts to fade.
How long Acyclovir Topical stays in your system
Common questions
How long does Acyclovir Topical stay in your system?
Acyclovir cream and ointment work mostly in the skin, and very little reaches your bloodstream. With the ointment, plasma levels are low or undetectable, and any drug that is absorbed is removed by your kidneys with a half-life of about 2 to 3 hours in adults with normal kidney function, so it is essentially gone within a day of your last dose. What you apply sits on the skin until it absorbs or washes off, usually within hours. Reduced kidney function slows clearance, but topical amounts stay small. Typical courses run 4 to 7 days depending on the product, and a sore that is not improving by then is worth a clinician visit.