Why is this drug prescribed?

Cogentin is given to help relieve the symptoms of "parkinsonism": the muscle rigidity, tremors, and difficulties with posture and balance that occur in Parkinson's disease and that sometimes develop as unwanted side effects of antipsychotic drugs such as Haldol and Thorazine.

Cogentin is an "anticholinergic" medication, a drug that controls spasms. It reduces the symptoms of parkinsonism, but it is not a cure.

Most important fact about this drug

When starting Cogentin, you may not feel its effect for 2 or 3 days. Symptoms caused by drugs such as Haldol and Thorazine are often temporary, so if drug-induced parkinsonism is your problem, you may need to take Cogentin for only a couple of weeks.

How should you take this medication?

Take Cogentin exactly as prescribed. Unlike some of the other antiparkinsonian medications, Cogentin acts over a long period of time. It is thus particularly suitable as a bedtime medication because it lasts through the night. Taken at bedtime, it may help a person regain enough muscle control to move and roll over during sleep and to arise unaided in the morning.

Cogentin causes dry mouth. Sucking on sugarless hard candy or sipping water can relieve this problem.

Cogentin can reduce the ability to sweat, one of the key ways your body prevents overheating. Avoid excess sun or exercise that may cause overheating.

--If you miss a dose...

Take it as soon as you remember. If it is within 2 hours of your next dose, skip the one you missed and go back to your regular schedule. Do not take 2 doses at once.

--Storage instructions...

Store away from heat, light, and moisture.

What side effects may occur?

Side effects cannot be anticipated. If any develop or change in intensity, inform your doctor as soon as possible. Only your doctor can determine if it is safe for you to continue taking Cogentin.

• Side effects may include:
  Blurred vision, bowel blockage, confusion, constipation, depression, dilated pupils, disorientation, dry mouth, fever, hallucinations, heat stroke, impaired memory, inability to urinate, listlessness, nausea, nervousness, numbness in fingers, painful urination, rapid heartbeat, rash, vomiting

Why should this drug not be prescribed?

Do not take Cogentin if you are sensitive to it or if you have ever had an allergic reaction to it or to any similar antispasmodic medication.

Do not take Cogentin if you have an eye condition called angle-closure glaucoma.

Some people who take certain antipsychotic medications develop tardive dyskinesia, a syndrome of involuntary movements of the mouth, jaw, arms, and legs. Cogentin should not be given to treat tardive dyskinesia; it will not help, and it may make the condition worse.

Cogentin should not be given to children under the age of 3; it should be used with caution in older children.

Special warnings about this medication

Do not drive or operate dangerous machinery while taking Cogentin, since the drug may impair your mental or physical abilities.

Be sure to tell your doctor if you have ever had tachycardia (excessively rapid heartbeats) or if you have an enlarged prostate; you will require especially close monitoring while taking Cogentin in these cases.

Tell your doctor if Cogentin produces weakness in particular muscle groups. For example, if you have been suffering from neck rigidity and Cogentin suddenly causes your neck to relax so much that it feels weak, you may be taking more Cogentin than you need.

If you have been taking another antiparkinsonism drug, do not stop taking it abruptly when you start taking Cogentin. If you are to stop taking the other drug, your doctor will have you taper off gradually.

Cogentin has a drying effect on the mouth and other moist tissues. If you take it along with another drug that also has a drying effect, you are at risk for anhidrosis (inability to sweat), heat stroke, and even death from hyperthermia (high fever). Chronic illness, alcoholism, central nervous system (brain and spinal cord) disease, or heavy manual labor in a hot environment can increase this risk. In hot weather, your doctor may lower your dosage of Cogentin.

Possible food and drug interactions when taking this medication

When taken simultaneously with an antipsychotic medication (Thorazine, Stelazine, Haldol, others) or a tricyclic antidepressant medication (Elavil, Norpramin, Tofranil, others), Cogentin has occasionally caused bowel blockage or heat stroke that proved dangerous or even fatal. If you are taking Cogentin along with an antipsychotic or with a tricyclic antidepressant, tell your doctor immediately if you begin to have any stomach or bowel complaint, fever, or heat intolerance.

Antacids, such as Tums, Maalox, and Mylanta, may decrease the effects of Cogentin. Do not take them within 1 hour of taking Cogentin.

Certain other drugs may also interact with Cogentin. Consult your doctor before combining Cogentin with any of the following:

Amantadine (Symmetrel)
Doxepin (Sinequan)
Antihistamines such as Benadryl and Tavist
Other anticholinergic agents such as Bentyl

Special information if you are pregnant or breastfeeding

If you are pregnant or plan to become pregnant, inform your doctor immediately. No information is available about the safety of taking Cogentin during pregnancy or while you are breastfeeding.

Recommended dosage

Your doctor will individualize the dose of Cogentin, taking into consideration your age and weight, the condition being treated, the presence of other diseases, and any physical disorder.

In general, the usual oral dose is 1 to 2 milligrams a day, but it can range from 0.5 to 6 milligrams a day.

Overdosage

Any medication taken in excess can have serious consequences. If you suspect symptoms of an overdose of Cogentin, seek medical attention immediately. Symptoms of overdose may include any of those listed in the "side effects section" (see above) or any of the following:

• 
  Blurred vision, confusion, coma, constipation, convulsions, delirium, difficulty swallowing or breathing, dilated pupils, dizziness, dry mouth, flushed, dry skin, glaucoma, hallucinations, headache, high blood pressure, high body temperature, inability to sweat, listlessness, muscle weakness, nausea, nervousness, numb fingers, painful urination, palpitations, rapid heartbeat, rash, shock, uncoordinated movements, vomiting