An antimuscarinic for Parkinson's and drug-induced movement problems
Benztropine
An antimuscarinic medicine used for Parkinson's disease and for movement problems caused by some other medicines.
What is Benztropine?
Benztropine is an antimuscarinic medicine used to help symptoms such as tremor, stiffness and muscle problems in Parkinson's disease, and to treat movement problems (such as stiffness or unusual muscle spasms) caused by certain other medicines, particularly some used for mental health. It works by helping to rebalance chemical signals in the brain that control movement. Its main drawbacks are antimuscarinic side effects such as dry mouth, blurred vision, constipation and confusion, which can be a particular problem in older people. It needs to be used with care in people with glaucoma.
Education and reference only. This is a plain-language guide to Benztropine — it deliberately contains no doses. Doses depend on the person, the brand and the reason for treatment, and belong with your prescriber. Always check the BNF, the product labelling (SmPC) and follow medical advice.
What it is
Benztropine is an antimuscarinic medicine, meaning it blocks the action of a brain chemical called acetylcholine. It is used to help some of the movement symptoms of Parkinson's disease, especially tremor and stiffness, and to treat movement problems — such as stiffness, restlessness or unusual muscle spasms — that can be caused by certain other medicines, particularly some antipsychotics used in mental health. It is taken to improve control of movement rather than to cure the underlying condition, and is used under medical supervision because of its side effects.
How it works
Movement is controlled in part by a balance between two brain chemicals, dopamine and acetylcholine. In Parkinson's disease, and when certain medicines block dopamine, this balance is upset, which can cause tremor, stiffness and abnormal movements. Benztropine works by reducing the activity of acetylcholine, helping to restore the balance and ease these symptoms. Because it acts on this chemical throughout the body, not just in the brain, it also produces the typical antimuscarinic side effects such as a dry mouth and blurred vision.
Company & origin
Originated / developed by: Various manufacturers.
An antimuscarinic medicine used in the UK to help tremor and stiffness in Parkinson's disease and to treat movement problems caused by certain other medicines.
What it treats
Conditions Benztropine is used for
Practical use
How to take Benztropine
General, dose-free guidance — always follow your prescriber's and the leaflet's specific instructions.
- Take it exactly as prescribed, usually by mouth, and do not change the dose yourself.
- Do not stop it suddenly, as movement symptoms can flare; any change should be made gradually under guidance.
- Take care in hot weather, as it can make it harder for your body to cool down.
- Tell your prescriber about other medicines, as several have similar drying effects that can add up.
- Report troublesome dry mouth, blurred vision, constipation, difficulty passing urine or confusion.
Weighing it up
Advantages & disadvantages of Benztropine
Advantages
- Helps tremor and stiffness in Parkinson's disease for some people.
- Effective for movement problems caused by certain other medicines, such as some antipsychotics.
- A long-established medicine with well-understood effects.
Disadvantages
- Commonly causes antimuscarinic effects such as dry mouth, blurred vision and constipation.
- Can cause confusion or memory problems, particularly in older people.
- Must be used with caution in glaucoma and cannot be stopped abruptly.
Practical use
Good to know
The main thing to expect with benztropine is a group of antimuscarinic side effects: dry mouth, blurred vision, constipation, difficulty passing urine and, especially in older people, confusion or memory problems. Because of this, it is used carefully in elderly people and is generally not a first choice for the tremor of Parkinson's in older patients. It can raise pressure in the eye, so it must be used with caution, and sometimes avoided, in people with a type of glaucoma. It can make the body less able to cope with heat, so take care in hot weather. It should not be stopped suddenly, as this can cause symptoms to flare. Tell your prescriber about other medicines, as several have similar drying effects that can add up.
Who should not take it / use with caution
- People who have had a serious allergic reaction to benztropine should not take it.
- It is used with caution, and sometimes avoided, in people with a type of glaucoma (raised eye pressure).
- It is used with care in older people and in those with problems passing urine, bowel obstruction or memory problems.
Monitoring
- Reviewing how well movement symptoms are controlled.
- Watching for antimuscarinic side effects, particularly confusion in older people.
- Checking eye pressure where there is a risk of glaucoma.
Side effects
- Dry mouth, blurred vision and constipation.
- Difficulty passing urine.
- Confusion, memory problems or drowsiness, especially in older people.
- Reduced ability to cope with heat, with a risk of overheating in hot weather.
Key interactions
- Other medicines with drying (antimuscarinic) effects can add to its side effects.
- It may affect how some other medicines, including certain ones for the stomach or mind, work.
- Alcohol and sedating medicines can add to drowsiness, so seek advice.
Available as: Tablets taken by mouth, and in some settings a solution for injection given by professionals.
Answers
Benztropine: frequently asked questions
What is benztropine used for?
It is used to help tremor and stiffness in Parkinson's disease and to treat movement problems, such as stiffness or muscle spasms, caused by certain other medicines like some antipsychotics.
Why does it dry my mouth?
Benztropine blocks a body chemical called acetylcholine, which also reduces saliva and causes other effects such as blurred vision and constipation; these are its typical side effects.
Is it safe for older people?
It is used with extra care in older people because it can cause confusion and memory problems, and is often not the first choice for them.
Can I stop it suddenly?
No. Stopping it abruptly can cause movement symptoms to flare, so any change should be made gradually under your prescriber's guidance.
Why does glaucoma matter?
Benztropine can raise the pressure inside the eye, so it is used with caution, and sometimes avoided, in people with a type of glaucoma.
The wider class
About Antimuscarinic (movement disorders)
Benztropine belongs to the antimuscarinic (movement disorders) class. For how the class as a whole works, its shared safety principles and monitoring, see the full guide.
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Authoritative sources
- BNF
- NICE CKS
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