NutriStack
Acyclovir and L-Lysine, a synergy.
L-lysine is used by some patients as adjunctive prophylaxis against herpes simplex recurrences, working by a different mechanism than acyclovir. Evidence is mixed and modest, but daily doses above 1-3 g have shown subjective benefit in some trials, with no known pharmacokinetic interaction with acyclovir or valacyclovir.
One pair, every claim cited. The two substances, the type, the mechanism, the recommendation, and the primary literature.
Same shape as the other 1,729 pairs in the public database.
From the interaction database
What the row says.
Every entry follows the same shape: what is happening, the mechanism, the recommendation, and the primary literature.
At a glance
- Pair type
- Synergy
- Evidence (highest tier)
- Emerging
- Source citations
- 2 sources
- Stack Score effect
- +2 to your Stack Score (per scored synergy row).
- Scope
- Supplement × Prescription
- Last verified
- May 30, 2026
Synergy · Emerging evidence
Synergy
What is happening. L-lysine is used by some patients as adjunctive prophylaxis against herpes simplex recurrences, working by a different mechanism than acyclovir. Evidence is mixed and modest, but daily doses above 1-3 g have shown subjective benefit in some trials, with no known pharmacokinetic interaction with acyclovir or valacyclovir.
Mechanism. HSV replication depends on arginine for capsid protein synthesis; lysine competes with arginine for intestinal transport and renal reabsorption, potentially lowering intracellular arginine availability. Acyclovir, in contrast, inhibits viral DNA polymerase, so the mechanisms are non-overlapping.
Recommendation. Lysine is reasonable as a complement to acyclovir for recurrent oral or genital HSV, typically at 1-3 g per day. Do not use it as a substitute for prescribed antivirals during an active outbreak.
Sources (2)
- Mailoo VJ, Rampes S. Lysine for herpes simplex prophylaxis: a review of the evidence. Integr Med (Encinitas). 2017;16(3):42-46. PMID 30881246
- Griffith RS, et al. Success of L-lysine therapy in frequently recurrent herpes simplex infection. Treatment and prophylaxis. Dermatologica. 1987;175(4):183-90. PMID 3115841
Stack Score
How this pair moves the number.
Effect on the composite score
If both Acyclovir and L-Lysine are in the same stack, this pair applies +2 to your Stack Score (per scored synergy row).
The full algorithm, the clamping rules, and four worked stacks are documented at /methodology/stack-score.
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