Benztropine, sometimes known as benzatropine outside of the US, is an FDA-approved therapy for treating all forms of parkinsonism. You should always consult a medical professional before taking Benztropine as it can be addictive and may have adverse side effects.

Benztropine brand names

Benztropine is available as a generic drug and also as a branded drug, under the name Cogentin.

What is benztropine prescribed for?

Benztropine is most commonly used to treat different types of parkinsonism. Parkinsonism is a term used to describe symptoms of tremors, muscle rigidity, and slow movements. Parkinson’s disease is the most widespread type of parkinsonism, but there are other rarer types of parkinsonism that can be caused by things such as medication, progressive brain conditions, and cerebrovascular disease.[1]

Benztropine can also be used to treat drug-induced movement disorders, dystonic reactions, and acute dystonic reactions (involuntary contractions of muscles in the extremities such as the face, neck, abdomen, pelvis, or larynx) improving muscle control and reducing muscle stiffness.[2]

How does benztropine work?

Benztropine works against acetylcholine and histamine receptors. In the CNS and smooth muscles, benztropine contends with acetylcholine at muscarinic receptors. By reducing central cholinergic effects it can improve the symptoms of Parkinson's disease.[3] It also blocks the effects of histamine in the brain, which does not serve the traditional function of managing allergies, rather it helps regulate cognition and arousal.

How is benztropine usually taken?

A dose of benztropine can be administered orally, intravenously, or through intramuscular routes. The oral route is preferred when addressing initial or acute symptoms of drug-induced parkinsonism. Benztropine therapy has cumulative effects so is often started with the lowest end of the dosages and may be gradually increased until optimal results are achieved. Oral doses are available in 0.5mg, 1mg, and 2mg and treatment usually starts with 0.5g, increasing up to 6mg over a period of up to 6 days.[2]

How long does benztropine stay in your system?

When administered orally, benztropine is gradually absorbed in the gastrointestinal tract and it reaches a peak concentration in around 7 hours. The elimination half-life of benztropine can vary significantly but is often around 36 hours.[4]

Benztropine side effects

It is not uncommon to experience side effects from benztropine, but some milder symptoms may go away on their own. If any of the common side effects persist for a long period of time, or you experience any of the potentially serious side effects listed below, you should consult a doctor immediately.

Common side effects:

  • Dry mouth
  • difficulty urinating
  • Blurry vision
  • Constipation
  • Nausea & vomiting
  • Loss of appetite
  • Dry skin

Potentially serious adverse reactions:

  • Skin rash
  • Irregular heartbeat
  • Fever
  • Confusion
  • Depression
  • Hallucinations or delusions
  • Changes in vision[6]

Benztropine precautions

There are a number of precautions you should take before using Benztropine:

  • Before taking any new medications, you should discuss any allergies you may have with your doctor or pharmacist. Your medical professional can help you review the list of ingredients in benztropine to avoid an allergic reaction.
  • You should also tell your doctor about any other medicines, supplements, or herbal products you are currently using or plan to take in conjunction with Benztropine
  • Make your doctor aware if you are pregnant, breastfeeding, or become pregnant whilst on benztropine
  • If you require medical surgery or dental surgery, let your doctor or dentist know that you are taking benztropine
  • Be aware that benztropine can make you drowsy, so do not drive or operate heavy machinery until you know you are safe to do so
  • Benztropine can cause your skin to become sensitive to sunlight, so try to avoid prolonged exposure to sunlight and wear protective clothing and sunscreen.[6]

Benztropine interactions

For the most part, benztropine should not be used if the patient has a history of sensitivity to benztropine mesylate or any component of the drug’s formula. Benztropine is contraindicated in patients with the following conditions:

  • Urinary retention, bladder obstruction, and prostatic hypertrophy – Benztropine must be used with caution for these conditions because it can mask their symptoms. Also, Benztropine may exacerbate urinary tract problems, particularly urine retention.
  • Closed-angle glaucoma – Benztropine should not be used on closed-angle glaucoma patients as it can cause mydriasis and cycloplegia. Also, it can indirectly cause a major increase in intraocular pressure.
  • Tachycardia – Benztropine should generally be avoided in cardiac patients as it can worsen tachycardia.
  • Tardive dyskinesia – Benztropine, as well as other drugs designed to treat parkinsonism, can heighten the symptoms of tardive dyskinesia.
  • Behavioral and psychological changes – Benztropine can affect both mental and physical abilities. The use of benztropine in patients with psychosis such as schizophrenia poses the risk of increasing their psychotic symptoms and behavioral changes. Anti-parkinsonian drugs can lead to toxic psychosis.
  • Dementia – Benztropine can intensify the symptoms of dementia so is not a recommended treatment for dementia patients.
  • Myasthenia gravis and autonomic neuropathy – Benztropine can cause muscle weakness so is best avoided in patients with myasthenia gravis or autonomic neuropathy.
  • Contact lenses – Anticholinergic drugs, such as benztropine, can cause dryness in the eyes, therefore they are not recommended for users of contact lenses as they may experience discomfort.[2]

Benztropine storage

Benztropine should be stored at room temperature, in a closed container, away from heat, moisture, and direct light. It also should not be frozen. Always keep medicine out of reach of children. Medicine that is out of date or no longer needed should be disposed of safely.[5]

What to do if you overdose on benztropine

In the case of a benztropine overdose, you should call the poison control helpline on 1-800-222-1222. Benztropine may cause an anticholinergic toxidrome, which may require supportive care. If the patient has collapsed, is seizing, is struggling to draw breath, or can’t be awakened you should call 911 immediately for medical attention.

Symptoms of a benztropine overdose can include:

  • Rash
  • Seizures
  • Coma
  • Heat stroke
  • Constipation
  • Confusion
  • Nervousness
  • Excitement
  • Muscle weakness
  • Blurred vision
  • Rapid heartbeat
  • Hallucinations
  • Dizziness
  • Dry mouth
  • Difficulty swallowing
  • Headache
  • Bloody vomit
  • Heartburn
  • Painful urination
  • Hot, flushed skin[6]

Frequently asked questions about benztropine

Is benztropine a benzodiazepine?

Benztropine is not a benzodiazepine, it belongs to the anticholinergic drug class.

Are there any alternatives to benztropine?

There are alternative medications for Parkinson's disease such as trihexyphenidyl and levodopa/carbidopa.[7] The mechanisms of these medications are different than those of benztropine but can still help with symptom management. Trihexyphenidyl is an antispasmodic, which will help with muscle rigidity and weakness. Levodopa increases dopamine in the brain to improve muscle flexibility and smoothness of movement.

Resources:

  1. NHS website. (2021, November 18). Causes. nhs.uk.https://www.nhs.uk/conditions/parkinsons-disease/causes/
  2. Ahuja A., & Abdijadid S. (2022, April 30) Benztropine. In StatPearls. Treasure Island (FL) StatPearls Publishing. Retrieved 2022, October fromhttps://www.ncbi.nlm.nih.gov/books/NBK560633/
  3. Guo MY, Etminan M, Procyshyn RM, Kim DD, Samii A, Kezouh A, Carleton BC, Association of Antidepressant Use With Drug-Related Extrapyramidal Symptoms: A Pharmacoepidemiological Study. Journal of clinical psychopharmacology. 2018 Aug;[PubMed PMID: 29901567]
  4. Benzatropine: Uses, Interactions, Mechanism of Action | DrugBank Online. (n.d.). DrugBank. Retrieved November 2, 2022, fromhttps://go.drugbank.com/drugs/DB00245
  5. Benztropine (Oral Route). (2022, June 20). Â.https://www.mayoclinic.org/drugs-supplements/benztropine-oral-route/proper-use/drg-20072652
  6. Benztropine: MedlinePlus Drug Information. (n.d.). Retrieved November 2, 2022, from https://medlineplus.gov/druginfo/meds/a682155.html
  7. Hanlon, J. T., Semla, T. P., & Schmader, K. E. (2015). Alternative Medications for Medications in the Use of High-Risk Medications in the Elderly and Potentially Harmful Drug-Disease Interactions in the Elderly Quality Measures. Journal of the American Geriatrics Society, 63(12), e8–e18. https://doi.org/10.1111/jgs.13807