Trihexyphenidyl
Also sold as: Artane, Pacitane
Prescription neededParkinson's, dizziness and migraine
Comes as:Tablet
Usual adult dose
Usual adult dose: 1 mg on the first day, raised slowly by the doctor to about 2 mg three times a day (usually 6 mg to 10 mg a day). It is also used for stiffness caused by antipsychotic medicines.
Your doctor may give you a different dose. Children's doses depend on weight.
Side effects
Common
- dry mouth
- blurred vision
- constipation
- dizziness
- nervousness
Serious — get help
Stop taking it and see a doctor straight away if you notice:
- difficulty passing urine
- confusion or hallucinations (especially in older people)
- fast heartbeat
- eye pain with red eye (glaucoma attack)
Do not take it, or take care, if
- Narrow-angle glaucoma
- Enlarged prostate or difficulty passing urine
- Bowel blockage
- Myasthenia gravis
- Older people with memory problems (use with caution)
Interactions
Medicines that can react with this one.
Moderate3 medicinesTake together only with care. Ask your doctor or pharmacist.
- Amitriptyline
Both have anticholinergic effects; together they increase confusion, constipation and urine retention.
- Atropine
Both have anticholinergic effects; together they increase confusion, fast heartbeat and urine retention.
- Chlorpromazine
Together they increase anticholinergic side effects such as dry mouth and confusion.