Parkinson’s Disease – Drugs Assignment
Introduction:
Parkinson’s disease is a progressive neurodegenerative disorder caused by loss of
dopamine-producing neurons in the brain, especially in the substantia nigra. It leads to tremors,
rigidity, bradykinesia, and postural instability.
1. Levodopa + Carbidopa
Mechanism of Action:
Levodopa converts into dopamine in the brain. Carbidopa prevents peripheral breakdown of
levodopa.
Dose & Timing:
100/25 mg, 3–4 times daily, taken with or after meals.
Side Effects:
Nausea, vomiting, dyskinesia, hallucinations, hypotension.
Contraindications:
Narrow-angle glaucoma, severe psychosis, MAO inhibitors.
2. Dopamine Agonists (Pramipexole, Ropinirole)
Mechanism:
Stimulate dopamine receptors directly.
Dose:
Pramipexole 0.125 mg three times daily (gradual increase).
Side Effects:
Sleepiness, hallucinations, impulse control disorders.
Contraindications:
Psychiatric illness, hypotension.
3. MAO-B Inhibitors (Selegiline, Rasagiline)
Mechanism:
Inhibit dopamine breakdown enzyme MAO-B.
Dose:
Selegiline 5 mg twice daily (morning preferred).
Side Effects:
Insomnia, headache.
Contraindications:
SSRIs (risk of serotonin syndrome).
4. COMT Inhibitors (Entacapone)
Introduction:
Parkinson’s disease is a progressive neurodegenerative disorder caused by loss of
dopamine-producing neurons in the brain, especially in the substantia nigra. It leads to tremors,
rigidity, bradykinesia, and postural instability.
1. Levodopa + Carbidopa
Mechanism of Action:
Levodopa converts into dopamine in the brain. Carbidopa prevents peripheral breakdown of
levodopa.
Dose & Timing:
100/25 mg, 3–4 times daily, taken with or after meals.
Side Effects:
Nausea, vomiting, dyskinesia, hallucinations, hypotension.
Contraindications:
Narrow-angle glaucoma, severe psychosis, MAO inhibitors.
2. Dopamine Agonists (Pramipexole, Ropinirole)
Mechanism:
Stimulate dopamine receptors directly.
Dose:
Pramipexole 0.125 mg three times daily (gradual increase).
Side Effects:
Sleepiness, hallucinations, impulse control disorders.
Contraindications:
Psychiatric illness, hypotension.
3. MAO-B Inhibitors (Selegiline, Rasagiline)
Mechanism:
Inhibit dopamine breakdown enzyme MAO-B.
Dose:
Selegiline 5 mg twice daily (morning preferred).
Side Effects:
Insomnia, headache.
Contraindications:
SSRIs (risk of serotonin syndrome).
4. COMT Inhibitors (Entacapone)
