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New Treatments for Parkinson's Disease

Parkinsonism is a movement disorder characterized by tremor, rigidity, bradykinesia, and postural instability. Parkinsonism is a relatively common disorder that occurs in all ethnic groups, with an approximately equal sex distribution. The most common variety, idiopathic Parkinson's disease (paralysis agitans), begins Exposure to certain toxins (eg, manganese dust).  Typical parkinsonism has occurred in individuals who have taken 1-methyl-4-phenyl-1,2,5,6-tetrahydropyridine (MPTP).

Tremor, rigidity, bradykinesia, and postural instability are the cardinal features of parkinsonism and may be present in any combination. There may also be a mild decline in intellectual function. The tremor of about four to six cycles per second.

Rigidity (an increase in resistance to passive movement) is responsible for the characteristically flexed posture seen in many patients, but the most disabling symptoms of parkinsonism are due to bradykinesia.

Treatment

Medical Measures: Drug treatment is not required early.

Amantadine–Patients with mild symptoms but no disability.

Anticholinergic drugs–Anticholinergics.

Benztropine mesylate (Cogentin) 16

Biperiden (Akineton) 212

Chlorphenoxamine (Phenoxene) 150400

Cycrimine (Pagitane) 520

Orphenadrine (Disipal, Norflex) 150400

Procyclidine (Kemadrin) 7.530

Trihexyphenidyl (Artane) 620

Levodopa–Levodopa, which is converted in the body.

Carbidopa, which inhibits the enzyme responsible for the breakdown of levodopa.

Sinemet, a commercially available preparation that contains carbidopa and levodopa in a fixed ratio (1:10 or 1:4).

The dyskinesias and behavioral side effects of levodopa are dose-related, but reduction in dose may eliminate any therapeutic benefit.

Levodopa therapy is contraindicated.

Dopamine agonists– Sinemet 25/100 (carbidopa 25 mg and levodopa 100 mg), one tablet three times daily when dopaminergic therapy is first introduced; the dose of Sinemet is kept constant, while the dose of the agonist is gradually increased. The two most widely used agonists are bromocriptine and pergolide, which are equally effective. The initial dosage of bromocriptine is 1.25 mg twice daily; this is increased by 2.5 mg at 2-week intervals until benefit occurs or side effects limit further increments. The usual daily maintenance dose in patients with parkinsonism is between 10 and 30 mg. Pergolide is similarly started in a low dose (eg, 0.05 mg daily) and built up gradually.

Bromocriptine and pergolide are contraindicated.

Pramipexole and ropinirole are two new dopamine agonists.

Selegiline–Selegiline is a monoamine oxidase B inhibitor that is sometimes used as adjunctive treatment for parkinsonism.

Surgical Measures: Thalamotomy or pallidotomy may be helpful for . Surgical implantation of adrenal medullary or fetal substantia nigra tissue into the caudate nucleus.