3 ms·Pretty sure I used to take L-lysine for cold sores. Maybe it has general antiviral properties.by collyw 7y agoPretty sure I used to take L-lysine for cold sores. Maybe it has general antiviral properties.wnmurphy 7y agoCertain viruses (herpetic) proliferate in an environment high in arginine, and low in lysine. High lysine/low arginine = suppression of replication.porker 7y agoIt's reputed to. It's been an alternative remedy recommended for shingles. Not seen a jot of evidence it works.