AHCC (Active Hexose Correlated Compound) is a proprietary extract obtained from the mycelia of certain species of Basidiomycete mushrooms. Its use for herpes (Herpes Simplex Virus, HSV) is primarily supported by limited scientific evidence rather than traditional use. AHCC is known for its purported immune-modulating effects. Several animal studies and in vitro experiments have shown that AHCC can enhance natural killer (NK) cell activity and modulate cytokine responses, which theoretically could help the immune system control herpes virus activity or reactivation.

However, direct evidence in humans is sparse. One notable animal study (2011, "AHCC enhances resistance to HSV-1 infection in mice through the induction of type I interferon") demonstrated that AHCC supplementation increased resistance to HSV-1 infection in mice, likely by promoting interferon production. Small pilot human studies have shown that AHCC may enhance general immune parameters in healthy adults or those under stress, but these studies have not specifically focused on herpes infection or outbreaks.

In summary, while preclinical research suggests a possible benefit of AHCC in supporting immune function relevant to herpes, there is currently insufficient clinical evidence to strongly support its use for herpes treatment or prevention in humans. Thus, the evidence is limited (rated 2 out of 5) and more rigorous clinical trials are needed.