Anticholinergic drugs
- These are classed to act through a similar mechanism as dopamine replacement drugs but they work on different sites of the brain. They work to block the action of acetylcholine, a neurotransmitter in the brain. In doing this, they act to restore a optimal balance between dopamine and acetylcholine in the brain. Anticholinergic drugs are mainly used in the treatment of younger patients who may have a tremor or rigity dominant form of Parkinson's disease or those who may be experiencing hemi-parkinsonism.
- There are limitations with the use of anticholinergics for example associations with memory impairment, confusion, blurred vision, urine retention and constipation. Due to these side effects they are not often used in patients over 70 years and are only popular in the initial single therapy treatment of Parkinson's.
- Finally, combinatory treatment using these and levodopa is not advised due to worsening the psychiatric and social side effects of levodopa. An example of an anticholinergic used in this way is benzhexol.