Lysine Aspartate and Herpes: Evidence Overview

Lysine, including its salt forms such as lysine aspartate, is sometimes used as a dietary supplement to support the management of herpes simplex virus (HSV) infections. The rationale for this use is based on the observation that lysine and arginine, two amino acids, compete for absorption and transport in the body. HSV replication appears to require arginine, and increasing lysine intake may theoretically reduce arginine availability, potentially inhibiting viral replication.

Several early clinical studies and case reports (primarily from the 1970s-1990s) suggested that lysine supplementation (often at doses of 1-3 grams daily) might reduce the frequency, severity, and healing time of herpes labialis (cold sores). However, the evidence is mixed and methodologically limited. A 2017 systematic review and meta-analysis concluded that there is some evidence for reduced recurrence rates with lysine supplementation, but the overall quality of evidence is low due to small sample sizes, lack of blinding, and inconsistent results.

Notably, most studies examined lysine itself rather than lysine aspartate specifically, but the bioavailable lysine is presumed to be the active component. Major clinical guidelines do not recommend lysine as standard therapy for herpes, and no high-quality, large-scale randomized controlled trials have definitively established its efficacy. Therefore, while there is some scientific rationale and limited evidence, its use is not robustly supported.