Bipolar Disorder Treatment Medications What to Know About Cogentin (Benztropine) An Anticholinergic Used to Treat Tremors By Marcia Purse Marcia Purse Marcia Purse is a mental health writer and bipolar disorder advocate who brings strong research skills and personal experiences to her writing. Learn about our editorial process Updated on May 10, 2022 Medically reviewed Verywell Mind articles are reviewed by board-certified physicians and mental healthcare professionals. Medical Reviewers confirm the content is thorough and accurate, reflecting the latest evidence-based research. Content is reviewed before publication and upon substantial updates. Learn more. by Steven Gans, MD Medically reviewed by Steven Gans, MD Steven Gans, MD is board-certified in psychiatry and is an active supervisor, teacher, and mentor at Massachusetts General Hospital. Learn about our Medical Review Board Print HeroImages/Getty Images Table of Contents View All Table of Contents Uses Dosage Common Side Effects Warnings and Interactions Cogentin (benztropine) is used for the treatment of Parkinson's disease and is in a class of drugs called anticholinergics. These drugs help rebalance irregular activity of acetylcholine neurotransmitters, which are crucial to brain and muscle function. Cogentin improves muscle control and has been shown to decrease rigidity and tremors associated with Parkinson's disease. It is also sometimes used to treat people with bipolar disorder who have developed parkinsonism. Parkinsonism in bipolar disorder is usually a side effect of antipsychotic medication, but it may also indicate idiopathic Parkinson's disease or co-occurring cerebrovascular disease. Cogentin comes in 0.5, 1, and 2 mg tablets to be taken orally, usually at bedtime, and in some cases, an injection is provided. One dose per day will typically suffice to treat symptoms of parkinsonism. Your doctor may start you on a small dose to see how you respond. Uses Medications often used to treat bipolar disorder, such as typical and atypical antipsychotic drugs, may cause drug-induced parkinsonism, the medical term for symptoms that mimic Parkinson's disease. Drug-induced parkinsonism may cause: A decrease in facial expressionsDifficulty starting and controlling movementSlowed movementSoft voiceStiffness of the trunk, arms, or legsTremor Recap Cogentin is FDA-approved to treat all forms of parkinsonism. It is used to treat symptoms of Parkinson's disease as well as extrapyramidal involuntary muscle movements caused by certain psychiatric drugs, including antipsychotics. Before Taking Before prescribing Cogentin, your doctor will evaluate your symptoms and any co-occurring medical conditions that may be affected by the use of this medication. They will also consider the other medications that you are currently taking before deciding if Cogentin is the right choice for your needs. Talk to your doctor about all medications, supplements, and vitamins that you currently take. While some drugs pose minor interaction risks, others may outright contraindicate use or prompt careful consideration as to whether the pros of treatment outweigh the cons in your case. Precautions and Contraindications Cogentin may interact with certain drugs, including antidepressants, sleeping pills, painkillers, antihistamines, anti-diarrheal medications, some antacids, and other medications. It's important that you speak with your doctor about any potential interactions. This includes telling your doctor about any supplements, herbs, or vitamins that you might also be taking. They may interact with the medication or might change the way the drug works in your body. Other Anticholinergics In addition to Cogentin, Artane (trihexyphenidyl) may also be prescribed to treat parkinsonism. Artane is available in tablet and liquid elixir forms. Be sure to tell your doctor if you are currently taking another anticholinergic medication. Dosage Your doctor will often start you at a lower dose and may gradually increase this dose to achieve the desired effect. Treatment is often initiated at a low dose and increased by 0.5 mg increments every five to six days until reaching a dose that provides optimal relief without excess side effects. A typical dose for adults is 1 to 4 mg once or twice per day. You should always take only the amount that your doctor has prescribed. Your specific dosage will depend on your needs, age, and weight. The timing of the dosage may also vary depending on your individual needs. For some individuals, a full dose taken right before bed produces the best results. Others find that they need a divided dose taken at different points during the day to help manage their symptoms. If you miss a dose, take it as soon as you remember unless it is almost time for your next dose. If that is the case, simply skip the missed dose. Do not take two doses at once. All listed dosages are according to the drug manufacturer. Check your prescription and talk to your doctor to make sure you are taking the right dose for you. Overdose If you or a loved one have potentially overdosed on Cogentin, call your local poison control center and/or 911 immediately. Symptoms of overdose include: Clumsiness or unsteadiness Severe drowsiness Severe dryness of mouth, nose, or throat Fast heartbeat Hallucinations (seeing, hearing, or feeling things that are not there) Mood or mental changes Seizures Shortness of breath or troubled breathing Trouble sleeping Warmth, dryness, and flushing of the skin Other Cogentin side effects not listed above may also occur in some patients. If you notice any other side effects, be sure to check with your doctor. Modifications Cogentin is not recommended for children below the age of three. For kids ages three and up, the use and dose must be determined by the child's doctor, but the recommended daily dose is 0.02-0.05 milligram per kilogram of body weight. Caution should be used when prescribing to older adults, since it may produce bladder, bowel, and central nervous system effects. How to Take and Store Cogentin tablets are taken by mouth either once a day as a single dose at bedtime or two to four times a day with meals. This medication should also be taken at least one hour before taking an antacid or anti-diarrhea medication, which may affect how Cogentin is absorbed. If you are taking Cogentin to treat extrapyramidal symptoms associated with the use of antipsychotics, your doctor may instruct you to take it on a regular schedule or to only take it as needed. The medication may cause sleepiness or dizziness. Do not drive or operate machinery until you determine how the medication will affect you. Cogentin should be stored at room temperature in a closed container. It should be kept away from direct sunlight, moisture, heat, and freezing temperatures. Always take your medication as directed by your doctor. Do not stop taking your medication without discussing it with your doctor first. Side Effects The following are common side effects of Cogentin. You should check with your doctor if they don't go away or worsen: Common Blurred vision Constipation Decreased sweatingDifficult or painful urination (especially in older men)DrowsinessDryness of mouth, nose, or throat The following are less common side effects of Cogentin. Dizziness or lightheadedness when getting up from a lying down or sitting positionEuphoriaHeadacheMemory impairments (especially in the elderly)NervousnessStomach upset or painUnusual excitement Severe Notify your doctor immediately if you experience any of the above rare side effects of Cogentin, as well as these below: ConfusionEye painSkin rashRapid heart rateHallucinations Warnings and Interactions Cogentin can also lead to serious health issues as well as drug interactions. This include: Allergic Reaction Allergic reactions may be mild or serious. Mild reactions include skin rashes that may go away if the dosage is decreased. Severe reactions can include swelling of the face and throat, trouble breathing, and hives. If you have a reaction, call your doctor or seek emergency services if symptoms are severe. Heat Stroke Cogentin can interfere with the body's ability to sweat and cool down. This can increase the risk for heat stroke, particularly when it is very hot outside. Staying well-hydrated and avoiding excessive sun exposure may help. Mental Health Effects This medication may also lead to symptoms of confusion, excitement, or hallucinations. These risks tend to be more serious in older adults, people who are taking larger doses of Cogentin, and people with a history of mental health conditions. Muscle Weakness People who take higher doses of Cogentin may be more likely to experience symptoms of muscle weakness. If you experience this symptom, talk to your doctor about lowering your dose. Drug Interactions Cogentin can also interact with a variety of medications and supplements. Taking this medication while using alcohol or other CNS depressants will lead to increased drowsiness. Other medications that may interact with Cogentin include tricyclic antidepressants and haloperidol. 9 Sources Verywell Mind uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy. Stoker T, Greenland J. Parkinson’s Disease - Pathogenesis and Clinical Aspects. Brisbane (AU): Codon Publications; 2018. doi: 10.15586/codonpublications.parkinsonsdisease.2018.ch9 Ward KM, Citrome L. Antipsychotic-Related Movement Disorders: Drug-Induced Parkinsonism vs. Tardive Dyskinesia-Key Differences in Pathophysiology and Clinical Management. Neurol Ther. 2018;7(2):233–248. doi:10.1007/s40120-018-0105-0 Dols A, Lemstra AW. Parkinsonism and bipolar disorder. Bipolar Disord. 2020;22(4):413-415. doi:10.1111/bdi.12888 Drugs.com. Cogentin Dosage. Shin HW, Chung SJ. Drug-induced parkinsonism. J Clin Neurol. 2012;8(1):15–21. doi:10.3988/jcn.2012.8.1.15 Drugs.com. Cogentin (benztropine) Drug Interactions. American College of Cardiology. benztropine. Medscape. Benztopine: Patient handout. Drugs.com. Cogentin Side Effects. Additional Reading Parkinson's Disease Society. Drug-induced Parkinsonism. By Marcia Purse Marcia Purse is a mental health writer and bipolar disorder advocate who brings strong research skills and personal experiences to her writing. See Our Editorial Process Meet Our Review Board Share Feedback Was this page helpful? Thanks for your feedback! What is your feedback? Other Helpful Report an Error Submit Speak to a Therapist Online Advertiser Disclosure × The offers that appear in this table are from partnerships from which Verywell Mind receives compensation.