For an immunocompetent adult with recurrent genital herpes on daily suppressive valacyclovir therapy, should the dose be taken a couple of hours before intercourse rather than at the same time each day?

Timing of Daily Valacyclovir for Suppressive Therapy

For daily suppressive valacyclovir therapy in immunocompetent adults with recurrent genital herpes, the medication should be taken at the same time each day—not timed around intercourse—because suppressive therapy works by maintaining steady antiviral drug levels that continuously reduce viral replication and asymptomatic shedding. 1, 2

How Suppressive Therapy Works

Daily suppressive valacyclovir functions through continuous viral suppression, not acute pre-exposure prophylaxis. The mechanism requires:

• Sustained therapeutic acyclovir concentrations that inhibit HSV replication throughout each 24-hour period, achieved through consistent once-daily dosing 1, 2
• Reduction of asymptomatic viral shedding by ≥75% through continuous drug presence, which cannot be achieved by intermittent pre-coital dosing 1, 2
• Steady-state pharmacokinetics that depend on regular daily administration at approximately the same time, not event-driven timing 3, 4

Why Pre-Intercourse Timing Is Ineffective

Taking valacyclovir "a couple hours before intercourse" fundamentally misunderstands the pharmacology of suppressive therapy:

• Valacyclovir requires consistent daily dosing to maintain therapeutic aciclovir levels; a single pre-coital dose does not provide adequate viral suppression 1, 4
• Asymptomatic viral shedding occurs unpredictably throughout the day and night, not just during sexual activity, so timing around intercourse leaves multiple windows of unprotected shedding 1, 2
• The drug's bioavailability and conversion to aciclovir are optimized through regular daily administration, not sporadic event-based dosing 3, 4

Correct Dosing Strategy

For immunocompetent adults with recurrent genital herpes:

• Patients with <10 recurrences per year: valacyclovir 500 mg once daily at the same time each day 1, 2, 5
• Patients with ≥10 recurrences per year: valacyclovir 1000 mg once daily at the same time each day 1, 2, 5
• HIV-infected patients (CD4+ ≥100 cells/mm³): valacyclovir 500 mg twice daily, not once daily 1, 2

Critical Counseling Points

Patients must understand that suppressive therapy:

• Does not eliminate asymptomatic viral shedding completely, meaning transmission risk persists even on daily therapy 1, 2
• Reduces but does not prevent transmission to sexual partners; condom use and disclosure remain essential 1, 2
• Requires consistent daily adherence to maintain efficacy; skipping doses or irregular timing reduces effectiveness 1, 2
• Should be reassessed after 1 year of continuous use to determine if ongoing suppression is needed, as recurrence frequency often declines over time 1, 2

Common Pitfall to Avoid

Do not confuse suppressive therapy with episodic treatment. Episodic treatment (500 mg twice daily for 3–5 days) is initiated at the first sign of an outbreak and is a completely different strategy from daily suppressive therapy 6, 7. Attempting to use episodic dosing in a "pre-intercourse" fashion provides neither adequate outbreak treatment nor effective suppression.