Benztropine mesylate, better known as Cogentin, is prescribed for movement disorders such as Parkinson's disease. It is also prescribed for medication-induced movement disturbances that appear with anti-psychotic medications such as Thorazine.
Cogentin is in the drug class called anticholinergics. It works by blocking the neurotransmitter acetylcholine. In the process of moving one's body, the muscles depend on a mix of two neurotransmitters to achieve fluid motion. Dopamine is one chemical involved and acetylcholine is the other. When a patient has Parkinson's, the serum levels of dopamine drop significantly. Also, this effect is seen in patients who are being treated with anti-psychotic medications. By blocking the production of acetylcholine, benztropine works in re-establishing the correct ratio of dopamine to acetylcholine. Cogentin is also recognized to have antihistamine effects and local anesthetic properties.
For Parkinson's Disease
The effects of benztropine on Parkinson's symptoms are an improvement in reducing tremors and a lessening of muscle rigidity. It also assists in preventing drooling, pain from muscle cramping, speech and writing problems and gait disorder. The dose taken for Parkinson's disease is usually started at 0.5mg; 1mg at bedtime. Some doctors increase the dose by 0.5mg every week until a maximum dosage of 6mg per day is reached. The dose can be taken as a single event or divided in equal amounts throughout the day.
Cogentin has been a useful treatment in patients with movement disorders directly linked to the side effects caused by anti-psychotic medications, especially those derived from phenothiazine and reserpine. These medications can cause akathisia, a condition in which patients are constantly moving. Common medications from phenothiazine are Thorazine, Prolixin, Serentil, Trilafon, Compazine, Mellaril, and Stelazine. Reserpine is made from the snakeroot plant and is rarely used because of its side effects. The recommended dose is 1 to 4mg once to twice daily.
Most people taking benztropine do not suffer side effects. Of the patients that do report side effects, elderly patients and those patients with progressive, organic brain disease are the highest risk group. Some of the more common side effects reported are dry mouth, visual disturbance, dizziness, rapid heartbeat, memory loss, listlessness, heat stroke, nausea, anxiety, numbness to fingers, retaining of urine, weakness and poor appetite. A few side effects are life-threatening and require immediate medical intervention. Those include anaphylaxis (severe, multi-system allergic reaction), confusion, chest pain, racing heartbeat, fever, uncontrolled body jerking, eye pain and severe constipation.
If the movement disorder is classified as a condition called tardive dyskinesia (unusual repetitive movements such as grimacing, lip smacking, lip puckering, continuous blinking), then benztropine is not only not effective, but may aggravate the condition. Men with a prostate disorder called benign prostatic hypertrophy (enlarged prostate) should use benztropine with caution since it can further impair urinary flow. Cardiac patients should be monitored more frequently due to the side effect of increased heart rate in some patients. Those patients with intestinal disorders such as colitis or a history of bowel obstruction are not ideal candidates for this medication because paralytic ileus (paralyzed area of bowel) has been connected to Cogentin. Alcohol can exacerbate any side effects observed with this drug. Benztropine is not considered safe for use in pregnant women, women who are breast-feeding, or children under 3 years of age. Although not strictly contraindicated, elderly patients in general need to be monitored for side effects.