Drugs Used For Parkinson's Disease
This article is excerpted from the APDA's booklet: Coping With Parkinson's Disease
What follows is a listing of all the major anti-Parkinson drugs, their effects and side effects, and their most common dosages. If you have specific questions about the drugs you are currently taking, please consult your physician.
Dopaminergics
Drugs used to replace or mimic the actions of dopamine.
Sinemet
Chemical name: Carbidopa-Levodopa
Indications: Helps all symptoms of PD. It is the primary anti-Parkinson drug. It is a combination of levodopa and carbidopa. Carbidopa allows levodopa to enter the brain, where it is converted to dopamine.
Dosages: Expressed as fractions, with top number referring to amount of carbidopa and the bottom number of levodopa, in milligrams. Common dosages are 10/100, 25/100, 25/250.
Range of daily dosage: 75-150 mg carbidopa; 75-1,000 mg levodopa.
Side effects: Nausea, daytime sleepiness, orthostatic hypotension, involuntary movements, decreased appetite, insomnia, cramping. In some patients, it may cause hallucinations, confusion, "on-off" effect.
Special considerations: Sinemet should be taken one hour before meals for maximium benefit. Should be taken with a whole glass of water or juice. Crackers should be taken if Sinemet causes stomach upset.
Sinemet CR
Indications: The same as Sinemet. It is a controlled-release form of Sinemet.
Dosages: 50/200, 25/100.
Range of daily dosage: 75-200 mg carbidopa; 200-1,000 mg levodopa.
Side effects: Same side effects as regular Sinemet.
Special considerations: May be especially useful in patients with "on-off" effects.
Anticholinergics
Anticholinergics block the action of the neurotransmitter acetycholine, helping to regain balance between acetylcholine and dopamine. Effective against rigidity and tremor, not against bradykinesia or akinesia. May be used alone early in the treatment of PD, or with Sinemet. Poor response or side effects with one anticholinergic does not exclude a trial with another one
Artane
Chemical name: Trihexyphenidyl HCL. Indications: Reduces tremor, drooling, and rigidity. This medication, like Cogentin, is a synthetic antispasmodic drug which has a relaxing effect on smooth muscle.
Dosages: Tablets of 2 mg, 5 mg, and long-acting 5 mg.
Range of daily dosage: 2-15 mg.
Side effects: Dry mouth, nausea, vomiting, confusion, difficulty swallowing or speaking, blurred vision, loss of appetite and/or weight, depression, hallucinations, constipation, urinary retention. Can worsen glaucoma.
Special considerations: Report side effects.
Cogentin
Chemical name: Benzotropine mesylate.
Qualities: Reduces tremor, rigidity, and drooling.
Dosages: 0.5 mg, 1 mg, 2 mg.
Range of daily dosage: 0.5-6 mg.
Side effects:Similar to Artane.
Special considerations: Use cautiously in elderly patients and patients with a history of confusion. Use cautiously in men with enlarged prostate gland.
Dopamine Agonists
Dopamine Agonists mimic the effects of dopamine by directly stimulating the dopamine receptors. Most commonly used early in combination with Sinemet. Agonists may also be started when patients are no longer responding satisfactorily to Sinemet used alone. Agonists may smooth out the fluctuating effect (wearing off or on-off ) often seen in Parkinson's patients on long term levodopa treatment. They are started at low doses and built up gradually over several weeks before therapeutic results are achieved. If dyskinesias increase, then a reduction in levodopa is indicated.
Parlodel
Chemical name: Bromocriptine mesylate.
Indications: Helps all aspects of Parkinson's disease. Used in combination with Sinemet to reduce symptoms and ameliorate severity of adverse reactions associated with long-term levodopa therapy, especially dyskinesias, wearing off and on-off.
Dosages: Tablet, 2.5 mg; capsule, 5 mg
Range of daily dosage: 1.25-30 mg
Side effects: Orthostatic hypotension, nausea, blurred vision, hallucinations.
Special considerations: May take several weeks for an effect to occur.
Permax
Chemical name: Pergolide mesylate.
Indications: Helps all aspects. Used in combination with Sinemet to reduce symptoms, may allow reduction in amount of Sinemet.
Dosages: Tablets 0.05 mg, 0.25 mg, 1 mg.
Range of daily dosage: 0.05-5 mg
Side effects: Similar to Parlodel.
Special considerations: Similar to Parlodel, may be effective in some patients who do not respond to Parlodel and vice versa.
Other Medications
Symmetrel
Chemical name: Amantadine.
Indications: An antiviral compound; it relieves tremors, rigidity, and bradykinesia.
Dosage: 100 mg capsules.
Range of daily dosage: 100-300 mg
Side effects: Swelling of the feet, loss of appetite, dizziness, anxiety, depression, hallucinations, urinary retention, blotchy legs, insomnia.
Special considerations: Should be used carefully in elderly patients.
Eldepryl
Chemical name: deprenyl, selegiline
Indications: An MAO-B inhibitor. Increases effect of dopamine by blocking the enzyme MAO-B that normally breaks down dopamine. Leads to increase in amount of dopamine in brain. Usually used in conjunction with Sinemet. There is a strong suggestion that Eldepryl may slow progression of PD
Dosage: Capsule, 5 mg
Range of daily dosage: 10 mg.
Side effects: Loss of appetite, nausea, dizziness, anxiety, insomnia. In some individuals it may cause confusion, hallucinations.
Inderal
Chemical name: Propranolol.
Indications: May reduce tremors.
Side effects: Lightheadedness, insomnia, weakness, depression, fatigue. In men it may cause impotence.
Trademarks
The following product names are registered trademarks of of Pharmaceutical Companies:
Product Company Artane Lederle Atamet Athena Ativan Wyeth Benadryl Parke-Davis Cogentin Merck Compazine Smith, Kline & Beecham Depakote Abbott Laboratories Desyrel Mead Johnson Diamox Lederle Domperidone Janssen Pharmaceutica Elavil Merck Eldepryl Somerset Haldol McNeil Inderal Ayerst Librium Roche Madopar Roche Pamelor Sandoz Parlodel Sandoz Permax Lilly Prolixin Bristol-Meyers Squibb Prozac Lilly Reglan Robins Ritalin Robins Sinemet DuPont Pharma Sinemet CR DuPont Pharma Stelazine Smith, Kline & Beecham Symmetral DuPont Pharma Thorazine Smith, Kline & Beecham Tofranil Geigy Valium Roche Wellbutrin Burroughs-Wellcome Xanax Upjohn