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Medically reviewed by Last updated on Mar 30, 2022.

What are other common names?

  • 2,6-diaminohexanoic acid
  • Alpha-epsilon-diaminocaproic acid
  • Hydrochlorure de L-Lysine
  • L-2,6-Diaminohexanoic Acid
  • L-Lysine
  • L-Lysine HCL
  • L-Lysine Hydrochloride
  • L-Lysine Monohydrochloride
  • Lisina
  • Lys
  • Lysine HCl
  • Lysine Hydrochloride
  • Lysine Monohydrochloride
  • Monochlohydrate de L- Lysine
  • Monochlohydrate de Lysine

What is this product used for?

Lysine helps with herpes infections and cold sores. It may help increase levels of calcium in your body.

What are the precautions when taking this product?

  • Always check with your doctor before you use a natural product. Some products may not mix well with drugs or other natural products.

  • Do not use this product if you are pregnant or plan to become pregnant soon. Use birth control you can trust while taking this product.

  • Do not use this product if you are breastfeeding.

  • Avoid taking a large amount of calcium supplements while taking lysine.

  • Take extra care if you are taking certain antibiotics called aminoglycosides. These are drugs like tobramycin, amikacin, or neomycin.

  • Do not take this product if you have high levels of lysine in your blood or urine.

  • Take extra care if you are taking arginine while taking lysine. Arginine can decrease the amount of lysine in your body and lysine can decrease the levels of arginine.

  • If you have blood sugar problems, keep hard candies, glucose tablets, liquid glucose, or juice on hand for low blood sugar.

  • Take extra care and check with your doctor if you have:

    • Kidney problems

    • Liver problems

    • Diabetes

What should I watch for?

  • Upset stomach

  • Rash

When do I need to call the doctor?

  • Signs of a very bad reaction. These include wheezing; chest tightness; fever; itching; bad cough; blue skin color; seizures; or swelling of face, lips, tongue, or throat. Go to the ER right away.

  • Signs of kidney problems. These include pain in your side, pain with passing urine, passing more or less urine than normal, feeling tired, or cloudiness or change in color of urine.

  • Very bad throwing up

  • Very bad belly pain

  • Very bad loose stools

Last Reviewed Date


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