A dopamine precursor is a substance that can be converted into dopamine in the body. Dopamine precursors are commonly used to treat the movement disorder Parkinson’s disease but also may be used to treat other conditions. Levodopa (also called L-Dopa) is an example of a dopamine precursor.

Levodopa is often combined with other substances (e.g., carbidopa) that help make the levodopa more effective while reducing side effects such as nausea and vomiting.

Patients are urged to tell their physician if they have been diagnosed with any medical condition, including allergies, diabetes, and kidney or liver disease. Certain medications also may interact poorly with dopamine precursors, including antacids, antidepressants, antihypertensives and MAO inhibitors. In addition, a diet especially high in protein or vitamin B6 may prevent levodopa from working properly.

Symptoms of overdose can be similar to the medication’s side effects, but are usually more severe. Patients should contact a physician immediately if they experience uncontrolled movements of the mouth, tongue, face, head, neck, arms and legs.

Dopamine precursors may present risks for people in certain populations, including pregnant and breastfeeding women, children and the elderly. As a result, people in these populations are urged to consult a physician and discuss the benefits and potential risks of taking dopamine precursors.