2 doctors weighed in:

Are there any side effects of l-lysine?

2 doctors weighed in
Dr. Rick Kirschner
General Practice
1 doctor agrees

In brief: High doses, maybe

Deficiency symptoms might include stomach cramps, diarrhea, hair loss weight loss, poor concentration, reproductive problems, kidney stones.
It can interact with a number of antibiotics to lethal effect. It could cause severe allergic reactions, (swelling of lips and tongue, or throat closure, difficulty breathing) old people need it more than young. Athletes use it.

In brief: High doses, maybe

Deficiency symptoms might include stomach cramps, diarrhea, hair loss weight loss, poor concentration, reproductive problems, kidney stones.
It can interact with a number of antibiotics to lethal effect. It could cause severe allergic reactions, (swelling of lips and tongue, or throat closure, difficulty breathing) old people need it more than young. Athletes use it.
Dr. Rick Kirschner
Dr. Rick Kirschner
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