Cogentin

Side effects associated with benztropine treatment include

• rapid heartbeat,
• confusion,
• depression,
• heat stroke,
• tiredness,
• memory problems,
• nervousness,
• numbness of fingers,
• psychotic symptoms,
• skin rash,
• constipation,
• nausea,
• vomiting,
• dry mouth,
• urinary retention, and
• blurred vision.

Manifestations

May be any of those seen in atropine poisoning or antihistamine overdosage: CNS depression, preceded or followed by stimulation; confusion; nervousness; listlessness; intensification of mental symptoms or toxic psychosis in patients with mental illness being treated with neuroleptic drugs (e.g., phenothiazines); hallucinations (especially visual); dizziness; muscle weakness; ataxia; dry mouth; mydriasis; blurred vision; palpitations; tachycardia; elevated blood pressure; nausea; vomiting; dysuria; numbness of fingers; dysphagia; allergic reactions, e.g., skin rash; headache; hot, dry, flushed skin; delirium; coma; shock; convulsions; respiratory arrest; anhidrosis; hyperthermia; glaucoma; constipation.

Treatment

Physostigmine salicylate, 1 to 2 mg, SC or IV, reportedly will reverse symptoms of anticholinergic intoxication.** A second injection may be given after 2 hours if required. Otherwise treatment is symptomatic and supportive. Maintain respiration. A short-acting barbiturate may be used for CNS excitement, but with caution to avoid subsequent depression; supportive care for depression (avoid convulsant stimulants such as picrotoxin, pentylenetetrazol, or bemegride); artificial respiration for severe respiratory depression; a local miotic for mydriasis and cycloplegia; ice bags or other cold applications and alcohol sponges for hyperpyrexia, a vasopressor and fluids for circulatory collapse. Darken room for photophobia.

Cogentin is part of the drug class:

• Ethers of tropine or tropine derivatives

Serious side effects have been reported with Cogentin including the following:

• Cardiovascular effects. Tell your healthcare provider right away if you have a fast, irregular, or pounding heartbeat.
• Digestive effects. Tell your healthcare provider right away if you experience dry mouth that is so severe that is causes difficulty speaking or swallowing or loss of appetite or weight.
• Nervous system changes. Symptoms of mental disorders may worsen with Cogentin treatment. Patients should be closely observed for mental status changes, especially at the beginning of treatment and when doses are increased.
• Cogentin can cause blurred vision, drowsiness, and dizziness. Do not drive or operate heavy machinery until you know how Cogentin affects you.

Do not take Cogentin if you:

• are allergic to Cogentin or to any of its ingredients
• are under 3 years of age

Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur:

• Abdominal or stomach cramps or pain
• aggressive and violent behavior
• being forgetful
• bloating
• burning while urinating
• confusion about identity, place, and time
• constipation
• decrease in frequency of urination
• decrease in urine volume
• diarrhea
• difficult or painful urination
• difficulty in passing urine (dribbling)
• difficulty with speaking
• difficulty with swallowing
• discouragement
• dizziness
• dry mouth
• extremely high fever or body temperature
• fast, pounding, or irregular heartbeat or pulse
• fast, shallow breathing
• fast, weak heartbeat
• feeling sad or empty
• fever
• headache
• hot, dry skin
• irritability
• lack of appetite
• lack of sweating
• listlessness
• loss of interest or pleasure
• mood or mental changes
• muscle cramps
• muscle weakness
• nervousness
• numbness of the fingers
• pale, clammy skin
• seeing things that are not there
• thirst
• tiredness
• trouble concentrating
• trouble with sleeping
• vomiting

Get emergency help immediately if any of the following symptoms of overdose occur:

• Blindness
• blurred vision
• change in consciousness
• cold clammy skin
• decreased vision
• dizziness
• eye pain
• holding false beliefs that cannot be changed by fact
• lightheadedness
• loss of consciousness
• muscle weakness
• nausea or vomiting
• no breathing
• nosebleeds
• numbness or tingling in the face, arms, or legs
• shakiness and unsteady walk
• sweating
• tearing
• unsteadiness, trembling, or other problems with muscle control or coordination
• unusual excitement, nervousness, or restlessness
• vision problems
• wheezing

Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

• Enlarged pupils
• loss of appetite
• skin rash
• weight loss

Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.

Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.

All drugs may cause side effects. However, many people have no side effects or only have minor side effects. Call your doctor or get medical help if any of these side effects or any other side effects bother you or do not go away:

• Hard stools (constipation).
• Upset stomach or throwing up.
• Dry mouth.

These are not all of the side effects that may occur. If you have questions about side effects, call your doctor. Call your doctor for medical advice about side effects.

You may report side effects to the FDA at 1-800-FDA-1088. You may also report side effects at http://www.fda.gov/medwatch.

• If you need to store Cogentin at home, talk with your doctor, nurse, or pharmacist about how to store it.

Rx only

Benztropine mesylate is a synthetic compound containing structural features found in atropine and diphenhydramine.

It is designated chemically as 8-azabicyclo[3.2.1] octane, 3-(diphenylmethoxy)-,endo, methanesul-fonate. Its empirical formula is C21H25NO•CH4O3S, and its structural formula is:

Benztropine mesylate is a crystalline white powder, very soluble in water, and has a molecular weight of 403.54.

Cogentin (benztropine mesylate) is supplied as a sterile injection for intravenous and intramuscular use.

Each milliliter of the injection contains:

Benztropine mesylate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 mg

Sodium chloride . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 mg

Water for injection q.s. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 mL

Cogentin possesses both anticholinergic and antihistaminic effects, although only the former have been established as therapeutically significant in the management of parkinsonism.

In the isolated guinea pig ileum, the anticholinergic activity of this drug is about equal to that of atropine; however, when administered orally to unanesthetized cats, it is only about half as active as atropine.

In laboratory animals, its antihistaminic activity and duration of action approach those of pyrilamine maleate.

For use as an adjunct in the therapy of all forms of parkinsonism (see DOSAGE AND ADMINISTRATION).

Useful also in the control of extrapyramidal disorders (except tardive dyskinesia – see PRECAUTIONS) due to neuroleptic drugs (e.g., phenothiazines).