An antimuscarinic for Parkinson's

Procyclidine

An antimuscarinic medicine used mainly to ease tremor in Parkinson's and movement problems caused by some other medicines.

What is Procyclidine?

Procyclidine is an antimuscarinic (anticholinergic) medicine used mainly to help tremor in Parkinson's disease, and to treat movement problems caused by certain other medicines such as antipsychotics. It does little for slowness of movement. It causes drying side effects such as dry mouth, blurred vision, constipation and difficulty passing urine, and can cause confusion, so it is generally avoided in older people. It should not be stopped abruptly.

Class: Antimuscarinics for Parkinson's · Brands: Kemadrin, Arpicolin

Education and reference only. This is a plain-language guide to Procyclidine — 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.

Class: Antimuscarinics for Parkinson's → Brands: Kemadrin, Arpicolin
Procyclidine (Antimuscarinics for Parkinson's) — Meds Global Health reference card with 2D molecular structure
Procyclidine — Antimuscarinics for Parkinson's. The image shows the active ingredient's 2D molecular structure.

What it is

Procyclidine is an antimuscarinic medicine used in Parkinson's disease, where it mainly helps with tremor rather than slowness of movement. It is also used to treat the stiffness, restlessness and abnormal movements that some other medicines, particularly antipsychotics, can cause. It works by blocking a chemical messenger called acetylcholine in the brain. It is taken by mouth and used under medical guidance.

How it works

In Parkinson's disease the loss of dopamine upsets the balance with another messenger, acetylcholine. Procyclidine blocks the action of acetylcholine, helping to restore some of this balance and easing tremor in particular. The same blocking action on acetylcholine elsewhere in the body causes its drying side effects, such as dry mouth and blurred vision.

Company & origin

Originated / developed by: Generic (long-established).

An antimuscarinic medicine used in the UK mainly for tremor in Parkinson's disease and for drug-induced movement problems.

Practical use

How to take Procyclidine

General, dose-free guidance — always follow your prescriber's and the leaflet's specific instructions.

  • Take it regularly as prescribed; it is used mainly to help tremor rather than slowness.
  • Expect possible dry mouth, blurred vision and constipation; sips of water and extra fibre can help, and report difficulty passing urine.
  • Be alert to confusion or memory problems, especially in older people, and report them to your team.
  • Do not stop it suddenly, as this can worsen symptoms; your team will reduce it gradually if needed.
  • If you miss a dose, take it when you remember unless it is nearly time for the next, then skip it and do not double up.

Weighing it up

Advantages & disadvantages of Procyclidine

Advantages

  • Can be helpful specifically for tremor in Parkinson's disease.
  • Useful for movement problems caused by some antipsychotic medicines.
  • Taken by mouth as a tablet or liquid, which is straightforward.

Disadvantages

  • Does little for slowness of movement, a major Parkinson's symptom.
  • Causes drying side effects such as dry mouth, blurred vision and urinary problems.
  • Can cause confusion, so it is generally avoided in older people.

Practical use

Good to know

Procyclidine mainly helps tremor and does relatively little for the slowness of movement that levodopa treats. Its antimuscarinic effects commonly cause dry mouth, blurred vision, constipation and difficulty passing urine, and it can cause confusion and memory problems, so it is generally avoided in older people. It is used with extra care in people with glaucoma or an enlarged prostate. Like other Parkinson's medicines it should not be stopped abruptly, as sudden withdrawal can worsen symptoms. Combining it with other drying medicines can make side effects add up.

Who should not take it / use with caution

  • People with closed-angle glaucoma should not usually take it.
  • People with significant urinary retention or an enlarged prostate should generally avoid it.
  • It is usually avoided in older people and in those with bowel obstruction or certain stomach problems.

Monitoring

  • Review of whether tremor or drug-induced movements are improving.
  • Watching for antimuscarinic effects such as urinary retention, constipation and confusion.
  • Extra care and review in older people and those on multiple drying medicines.

Side effects

  • Dry mouth, blurred vision and constipation are common antimuscarinic effects.
  • Difficulty passing urine, dizziness and sometimes a fast heartbeat.
  • Confusion, memory problems or hallucinations, especially in older people.

Key interactions

  • Other antimuscarinic medicines add to dry mouth, constipation and urinary problems.
  • Sedating medicines and alcohol can increase drowsiness and confusion.
  • Tell your prescriber about all medicines, as several drying medicines together need care.

Available as: Tablets and an oral liquid.

Answers

Procyclidine: frequently asked questions

What does procyclidine help most with?

It is used mainly for tremor in Parkinson's disease and for movement problems caused by some other medicines; it does little for slowness of movement.

Why might it be avoided in older people?

Its antimuscarinic effects can cause confusion and memory problems, which are more likely and more troublesome in older people, so it is often avoided in that group.

Why do I get a dry mouth and blurred vision?

These are antimuscarinic effects from blocking acetylcholine; they are common and usually settle, but report difficulty passing urine.

Can I stop it suddenly?

No. Stopping abruptly can worsen symptoms, so any change should be made gradually under your team's guidance.

Can I take it with glaucoma or prostate problems?

It needs caution and is often avoided in closed-angle glaucoma and significant prostate enlargement, so tell your prescriber about these.

Building a medicines information resource?

We create evidence-led, dose-free drug and formulary references for teams.

☎ Call Get a Proposal