Lysine Side Effects
Applies to lysine: oral tablet
Get emergency medical help if you have signs of an allergic reaction: hives; difficulty breathing; swelling of your face, lips, tongue, or throat.
Although not all side effects are known, lysine is thought to be possibly safe when taken for up to a year.
Common side effects may include:
stomach pain and diarrhea.
This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects.
Some side effects may not be reported. You may report them to the FDA.