Some Effective Medications for Parkinson’s Disease

Levodopa

Levodopa is a natural chemical that passes into human brain and then converted into dopamine and it is very effective medication for PD. Carbidopa when combined with levodopa, which protect levodopa form conversion into dopamine outside brain and minimize side effects such as nausea or light-headedness (orthostatic hypotension).

As disease progresses after years the benefit form levodopa may become less stable. After taking higher dose of Levodopa , person may experience dyskinesia (involuntary movements). Carbidopa-levodopa infusion The US FDA approved a drug called Duopa in 2015. This medication is made up of carbidopa and levodopa. However, it's administered through a feeding tube that delivers the medication in a gel form directly to the small intestine. The patient has severe PD but who still respond to carbidopa-levodopa, but has many fluctuations in their response, are treated with Duopa. Blood level of two drugs remain same due to continuous infusion of Duopa. [18]2)

Dopamine agonists

Doamine antagonist cannot change into dopamine but they mimic dopamine effects in brain and they are not more effective but can control symptoms of disease. They can be used with Levodopa to smooth the off-and-on effects of Levodopa. Dopamine agonists include pramipexole (Mirapex), ropinirole (Requip) and rotigotine. Apomorphine is used for quick relief which is short acting injevtable dopamine agonist.Some of the side effects of dopamine agonists are similar to the side effects of carbidopa-levodopa, but also include hallucinations, sleepiness and compulsive behaviors such as hyper sexuality, gambling and eating. [19]

MAO-B Inhibitors

Selegilie and Rasagiline are MAO_B inhibitors which prevent the breakdown of dopamine in brain by inhibiting the monoamine oxidase B which is brain enzyme which metabolized brain dopamine. Nausea and insomnia are side effects of these drugs. The risk of hallucination may increase when it given with carbidopa-levodopa. Normally it is not given with most antidepressant but in some rare cases it is used. [19]4) Catechol-O-methyltransferase (COMT) inhibitors Primary medication of this class is Entacapone.

The effect of levodopa therapy mildly prolongs due to use of this medication by blocking an enzyme which breakdown dopamine. Increased risk of involuntary movements, and diarrhea are side effects. Another drug of this class which is rarely prescribed due to the risk of serious liver damage and liver failure is Tolcapone. [19]

Anticholinergic

To control the tremor associated with PD this drugs are used from many years. Benztropine or trihexyphenidyl are available medication. Impaired memory, confusion, hallucination, constipation, dry mouth and impaired urination are side effects. [19]

Amantadine

To provide short term relief from symptoms of PD this drug is used. It may give along with Carbidopa-Levodopa therapy at later stages of PD which results in control involuntary movements induced by Carbidopa-Levodopa. A purple mottling of skin, ankle swelling and hallucination are side effects of dug.