Dopamine, Parkinson's and Levodopa (L-DOPA) : What are they? How do they work together? Are there side effects of L-DOPA?

Neurotransmitters like Dopamine, behave like chemical messengers in the nervous system, by facilitating signal transmission between consecutive neurons or neurons to muscles. These molecules are essential to aid communication within our body, and are crucial to the diverse physical processes that go on in our body every day: mood regulation, cognition and motor control.

Dopamine plays a very important role in regulating motor control and movement of muscles, especially in the case of controlled and smooth movements. People with Parkinson’s disease tend to lack this. Parkinson’s disease is a neurodegenerative disorder which shows progressive loss in the dopamine-generating neurons in brain tissue. The reduction in dopamine in the brain results in various symptoms like tremors, rigidity in movement, and something known as bradykinesia (basically slower movement than usual.)

In persons with Parkinson’s, dopamine supplementation in the brain is a key aspect to their treatment approaches; Medications like L-DOPA (Levodopa) are most often used to increase the levels of dopamine in brain tissue. Levodopa, in itself, is a precursor of dopamine; When it passes the blood-brain barrier, it can be converted into dopamine by our body.

L-DOPA tends to be administered orally in the form of tablets. Once levodopa reaches the brain, it is converted into dopamine through digestion by an enzyme called ‘aromatic L-amino acid decarboxylase’. Newly formed dopamine due to the L-DOPA then helps to alleviate the symptoms of Parkinson’s by improving motor relay, mobility and overall function of neurons.

However, it is important to note that L-DOPA cannot be consumed on a regular basis for a long period of time, as it can lead to a variety of side effects, if not kept in check; these include: nausea, vomiting, dyskinesias (basically meaning abrupt or involuntary movement), orthostatic hypotension (when your eyes go black when you stand and feel dizzy), hallucinations, psychosis, sleep disturbances (insomnia, for example), skin rashes, and over time, the efficacy of the medicine on the root cause also decreases, as your body develops a kind of resistance to the medicine.

By working with a healthcare provider, most families and patients with Parkinson’s disease can manage it through the supplementation of L-DOPA, although heavy reliance on the medication can lead to severe problems for the patient consuming it. All in all, L-DOPA is an effective medication, but it most be used in moderation with consultation of doctors.