Which neurotransmitter is depleted in Parkinson’s disease?

Parkinson’s disease results from a deficiency of the neurotransmitter dopamine in certain brain neurons that regulate motor activity. Parkinson’s disease is characterized by stiff posture, tremors, slowness of movement, postural instability, and reduced spontaneity of facial expressions. There is no cure for Parkinson’s disease, but certain medications provide relief from the symptoms by increasing the amount of dopamine in the brain. Patients are usually given levodopa combined with carbidopa. Carbidopa delays the conversion of levodopa into dopamine until it reaches the brain. Nerve cells can use levodopa to make dopamine and replenish the brain’s dwindling supply.