From the Research
L-Lysine may help alleviate canker sores for some people, though scientific evidence is mixed, and the most recent study suggests its potential in controlling viral infections by competing with arginine 1. The proposed mechanism involves lysine's competition with arginine, an amino acid that may trigger herpes simplex virus replication (which some believe is related to canker sores). Some key points to consider when using L-Lysine for canker sores include:
- A typical recommended dosage is 1,000-3,000 mg daily during an outbreak, reducing to 500-1,000 mg daily for prevention, as seen in studies such as 2 and 3.
- For acute treatment, start with 1,000 mg three times daily until symptoms improve, then reduce to a maintenance dose.
- L-lysine supplements are available as tablets, capsules, or powder and are best taken on an empty stomach with water.
- Foods high in lysine include meat, cheese, fish, eggs, and legumes, while foods high in arginine (which some suggest limiting) include nuts, chocolate, and certain grains.
- Side effects are generally mild but may include stomach discomfort or diarrhea, with a provisional no-observed-adverse-effect level of 6000 mg/person/day 4.
- If you have kidney disease or liver problems, consult your healthcare provider before taking lysine supplements. It's essential to note that individual results may vary, and while some people report significant benefits, others notice little effect. The most recent and highest quality study on the topic, a narrative literature review published in 2022, highlights the potential of L-Lysine in controlling viral infections by competing with arginine 1. However, more studies are needed to fully understand the effects of L-Lysine on canker sores and to determine the optimal dosage and treatment duration.