Due to decrease in excessive cholinergic activity (due to decreased dopamine) always given in combination with levo dopa.
Also given in drug induced Parkinsonism.
Never give dopamine agonist drugs as receptors are already occupied.
Adverse effects
- Dryness in mouth
- Decreased lacrimation
- Blurred vision
- Constipation
- Difficulty in urination
- Tachycardia
In Parkinson’s disease excessive salivation occurs, so these drugs have more effects on tremors and rigidity, but no effect on hypokinesia.
Always given in combination with dopamine agonists in Patients having parkinsonism. In drug induced, can be used alone.
Start at lower dose, which may be increased.
Antihistamines and anti-cholinergics
Due to anticholinergic effects, antihistamines are combined with anticholinergics.