What is Levodopa?

Levodopa, also known by its brand name Sinemet, is the primary medication used to treat Parkinson's motor symptoms. Levodopa is a precursor to dopamine. When taken orally, levodopa crosses the blood-brain barrier and is converted by remaining dopamine neurons to dopamine. This replaces the loss of natural dopamine production caused by Parkinson's and helps improve motor function.

Levodopa was discovered in the 1960s and revolutionized Parkinson's treatment. Prior to levodopa, patients faced severe disability. With levodopa, many experienced dramatic improvement in symptoms such as tremors, rigidity, slow movement, and difficulty walking. Levodopa quickly became the standard first-line treatment for Parkinson's. It remains so today due to its remarkable effectiveness compared to other medication options.

How Does Levodopa Work?

When Parkinson's destroys dopamine-producing neurons, less dopamine is available to transmit signals within motor circuits in the brain. This leads to the motor symptoms of Parkinson's. Levodopa works by providing a boost of dopamine in these deficient pathways. Once in the brain, levodopa is converted to dopamine by dopamine decarboxylase, an enzyme found in dopamine and serotonergic neurons.

The new dopamine can then bind to and stimulate dopamine receptors in areas like the striatum that normally receive dopamine input from the substantia nigra. This replaces the loss of natural dopamine signaling and improves communication between brain regions involved in motor control. Clinical studies have found levodopa effectively reduces tremor, rigidity, slowness, and other Parkinson's motor impairments for several hours after each dose.


Get More Insights on Levodopa