What You Need to Know About L-dopa Supplements

Reviewed by Terri Forehand RN
Woman with supplements

L-dopa is an amino acid derived from legumes. It's known for its health benefits but taking the supplement is not without risk. If you're considering using L-dopa, you need to know a few important things first.


L-dopa is short for l-3, 4-dihydroxphenylalanine. According to Chemical and Engineering News, the substance was first isolated in 1913 from broad beans (Vicia faba, also known as fava bean). L-dopa is also found in high concentrations in velvet beans (Mucuna pruriens, also known as Cowhage).

L-dopa was determined to be inactive until 1927 when biochemists discovered it caused a drop of blood pressure in rabbits. It was later shown to decarboxylize into dopamine, a neurotransmitter responsible for thinking, movement, pleasure and other emotions, and was found in tissues throughout the body.

By the early 1960s, scientists realized loss of dopamine played a part in Parkinson's disease, a degenerative neurological disorder, and began trials using L-dopa in Parkinson's patients. The trials were a success and led to L-dopa becoming a primary Parkinson's treatment that is still used today. However, L-dopa isn't only used to treat Parkinson's disease. It's believed to help other conditions as well.


L-dopa is believed to help several medical conditions including the following:

Parkinson's Disease

L-dopa's reputation was initially earned as a treatment for Parkinson's disease. According to the University of Maryland Medical Center, Parkinson's treatments are meant to increase dopamine levels in the brain. Prescription L-dopa drugs such as Levadopa are often the first treatment of choice for Parkinson patients.

Male Fertility

Mucuna pruriens helps recover sperm loss, according to an abstract published by the American Society of Reproductive Medicine. Treatment of 75 infertile men with Mucuna pruriens significantly improved sperm count and motility. As a result, the study concluded that "treatment with M. pruriens regulates steroidogenesis and improves semen quality in infertile men."

A separate study performed on rats determined that L-dopa is the primary reason for Mucuna pruriens' pro-sperm effects.

Increases Human Growth Hormone

It's believed that decreases in Human Growth Hormone (HGH) are at least partially responsible for many of the signs of aging including low libido, loss of muscle and bone mass, and fatigue. According to Doctor's Relief, research shows that L-dopa stimulates and elevates HGH in the body.

May Relieve PTSD

Ongoing studies are underway to determine whether or not L-dopa helps relieve Post Traumatic Stress Disorder (PTSD) symptoms. According to a Medical Research article, researchers believe L-dopa could help prevent previous fear associations that might occur under stressful circumstances.

It's believed that because L-dopa stimulates both the brain's pleasure center and memory formation, people taking L-dopa might develop a stronger second memory to replace the negative primary one.

Restless Leg Syndrome

L-dopa has been studied as a remedy for Restless Leg Syndrome. Several small studies have been performed. Most showed that L-dopa decreased leg movement and some reported better sleep. However, results were inconsistent and some severe side effects were reported. As a result, more research is needed to determine the efficacy of L-dopa for treating RLS.

Risks and Precautions

The prescription form of L-DOA is called Levadopa and is primarily used to treat Parkinson's. Drugs.com reports side effects that range from mild to severe and include:

  • Abnormal thinking
  • Anxiety and/or agitation
  • Clumsiness
  • Confusion
  • Dizziness
  • Faintness
  • Hallucinations
  • Nausea and/or vomiting
  • Numbness
  • Uncontrolled body movements
  • Blurred vision
  • Difficulty urinating
  • Fast or irregular heartbeat/arrhythmias
  • Rash
  • Unusual weight gain or loss
  • Back or leg pain
  • Bloody stools
  • High blood pressure
  • Low blood pressure
  • Convulsions
  • Pale skin
  • Prolonged erection
  • Stomach pain
  • Darkening of bodily fluids
  • Bitter taste in the mouth
  • Burning sensation of tongue

Consult Your Doctor Before Using

Prescription Levadopa can only be obtained by a doctor. It's usually combined with Carbadopa, a drug that helps reduce Levadopa's side effects and helps more Levadopa get into the brain. Drugs.com indicates that the initial dose of Levadopa to treat Parkinson's is 250 to 500 mg twice a day. Maintenance amounts are 3000 to 6000 mg divided over three times a day.

Non-Prescription Options

There are many L-dopa supplements available online and in natural food stores. These are often sold as a pill or extract under a Murcuna pruriens label, but you should consult your doctor before taking them. The correct dosage is critical to lessening the risk of side effects and you should be monitored while taking the supplements since prolonged use may increase your chances of developing a problem.

Medical Advice Necessary

In addition, taking Mucuna pruriens supplements alone for its L-dopa content may be a moot point. According to WebMD, unless certain chemicals are present (such as with prescription Levadopa and Carbadopa), most L-dopa is broken down in the body before it ever reaches the brain. WebMD also states that there is not enough scientific evidence to determine the appropriate dosage for Mucuna pruriens. Your doctor can best advise you of the potential risks and benefits.

Was this page useful?
Related & Popular
What You Need to Know About L-dopa Supplements