Valacyclovir
Valacyclovir. L-valyl ester prodrug of acyclovir — first-pass valine hydrolysis improves oral F from ~15% (acyclovir) to ~55% (valacyclovir).… Oral half-life 2.8 h.
L-valyl ester prodrug of acyclovir — first-pass valine hydrolysis improves oral F from ~15% (acyclovir) to ~55% (valacyclovir). Same downstream antiviral mechanism. Once-daily HSV suppression dosing supported by improved exposure.
PK: THIS RECORD IS A WRONG-ANALYTE HYBRID and now says so. F is verbatim at 54.2% but it is the yield of ACYCLOVIR per mole of valaciclovir swallowed, not valaciclovir absorption; mw 324.34 is the prodrug; and the stored 3 h and 50 L were byte-identical copies of the acyclovir record. Valaciclovir itself is under 0.5% of the dose in urine and undetectable in plasma after 3 hours — and that detection-limit statement is exactly where the stored 3 h came from. Every parameter here therefore describes acyclovir: half-life 2.8 h (PMID:8245883, review-grade) and the derived acyclovir volume. This is NOT a double-count with the acyclovir record: 20% is oral acyclovir and 54.2% is oral valaciclovir, two products in two studies. ka 2.1 /h dropped. The clean fix is structural — either re-key this record to acyclovir mass or fold it into acyclovir as a third route — and is logged rather than done here. MASS: the stored molecular weight described the PARENT while pk_analyte declares the metabolite, so the one field that must name a single species named the wrong one. LATENT RATHER THAN LIVE — this record carries no occupancy rows and is no other record interaction perpetrator — but it is one authored edge away from being live, because both consumers of the field (the micromolar-to-mass conversion for a kinetics edge, and the affinity the app renders from a stored occupancy concentration) want the species that actually circulates, which is the species pk[] already describes.
Pharmacokinetics
- Oral — t½ 2.8 h · F 54% · Vd 70.7 L
Sources: PMID:8593015, PMID:8245883, PMID:6355048