Pramipexole is a non-ergot dopamine agonist used for the treatment of Parkinson's Disease and moderate-to-severe primary Restless Legs Syndrome (RLS). As a dopamine receptor agonist, while it improves symptoms, it may also cause a series of adverse reactions.

What Are the Side Effects of Pramipexole?

Common Adverse Reactions in Patients with Parkinson's Disease

Adverse reactions with an incidence of ≥5%: nausea (28%), dizziness (25%), somnolence (22%), insomnia (17%), constipation (14%), fatigue (14%), and hallucinations (9%).

Common Adverse Reactions in Patients with Restless Legs Syndrome

(1) Common adverse reactions with an incidence >5%: nausea (16%) and somnolence (6%).

(2) Headache (16%).

(3) Fatigue (9%).

(4) Constipation (4%).

Serious Side Effects of Pramipexole That Require Vigilance

1. Sudden Sleep Onset During Daily Activities

(1) During treatment with pramipexole, patients may experience sudden sleep onset without any warning, including during daily activities such as driving, talking, or eating.

(2) This condition may still occur even one year after the start of treatment.

2. Impulse Control Disorders

(1) The use of dopamine agonists, including pramipexole, may lead to intense urges such as pathological gambling, sexual urges, shopping urges, and binge-eating urges, and patients may be unable to control these urges.

(2) In some patients, these urges resolve after dose reduction or drug discontinuation.

3. Orthostatic Hypotension

(1) Dopamine agonists may impair the blood pressure regulatory system, leading to orthostatic hypotension, especially during the dose escalation phase.(2) It manifests as symptoms such as dizziness, nausea, syncope, and sweating.

4. Withdrawal Syndrome

(1) Hyperthermia.

(2) Confusion.

(3) Severe muscle rigidity.

(4) Apathy.

(5) Anxiety.

Precautions for Pramipexole Administration

1. Medication Use in Special Populations

(1) Elderly patients: The clearance rate decreases by approximately 30%, and the half-life is prolonged to about 12 hours.

(2) Pregnant women: Use only when the potential benefits outweigh the risks.

(3) Lactating women: Consider discontinuing the drug or stopping breastfeeding. For hepatic impairment: No dose adjustment is required for mild to moderate impairment; data on patients with severe impairment is limited.

(4) Pediatric patients: The efficacy has not been established.

2. Drug Interactions

(1) Cimetidine can increase the AUC of pramipexole by 50% and prolong the half-life by 40%.

(2) Dopamine antagonists (e.g., phenothiazines, butyrophenones, metoclopramide) may reduce the efficacy of pramipexole.

(3) Concurrent use with other central nervous system depressants (e.g., alcohol) may increase sedative effects.

3. Administration Guidelines

(1) May be taken with food to reduce the occurrence of nausea.

(2) Swallow the tablets whole; do not crush, chew, or dissolve them.

(3) If a dose is missed, do not take a double dose; instead, take the prescribed dose at the next regular time.

(4) Discontinuation of the drug should be done by gradually reducing the dose; do not stop suddenly.

(5) When switching from enzyme replacement therapy (ERT) to pramipexole, administration can be initiated 24 hours after the last ERT dose.