Levodopa/Carbidopa/Entacapon Neuraxpharm (Carbidopa, Entacapone, Levodopa)

Levodopa/Carbidopa/Entacapone is used in the management of Parkinson's disease and related motor fluctuation syndromes.

• Parkinson's disease (early stage): improves motor symptoms when used with other dopaminergic agents.
• Parkinson's disease (advanced with motor fluctuations): reduces OFF periods and increases ON time.
• Parkinson's disease (adjunct therapy): enhances overall dopaminergic response and stabilises symptom control.

• Levodopa crosses the blood‑brain barrier and is converted to dopamine, restoring deficient neurotransmission. Carbidopa inhibits peripheral dopa decarboxylase, preventing premature conversion of levodopa and increasing its central availability. Entacapone blocks catechol‑O‑methyltransferase (COMT), prolonging levodopa plasma half‑life and enhancing its therapeutic effect.

Adverse reactions may occur with any dose of Levodopa/Carbidopa/Entacapone.

Common Side Effects

• Nausea: mild to moderate gastrointestinal upset.
• Dizziness: often related to orthostatic changes.
• Headache: transient and usually self‑limiting.
• Insomnia: difficulty falling or staying asleep.
• Orthostatic hypotension: drop in blood pressure upon standing.
• Dry mouth: reduced salivation.

Serious or Rare Side Effects

• Dyskinesia: involuntary movements that may be disabling.
• Hallucinations: visual or auditory disturbances, especially in older patients.
• Severe hypotension: marked blood pressure fall requiring medical attention.
• Neuroleptic malignant syndrome: rare but life‑threatening reaction.
• Anaphylaxis: acute allergic response with rash, swelling, or breathing difficulty.

Before initiating therapy, consider patient‑specific factors and monitor appropriately.

• Renal impairment: assess kidney function and adjust dose if necessary.
• Hepatic impairment: use with caution and monitor liver enzymes.
• Cardiovascular disease: monitor blood pressure and heart rate regularly.
• Psychiatric history: watch for emergence of hallucinations or confusion.
• Concomitant MAO‑B inhibitors: avoid combination to prevent hypertensive events.
• Store at room temperature: keep in the original container, protect from moisture and light.

Levodopa/Carbidopa/Entacapone may interact with several medicines; review patient medication lists.

Major Interactions (Avoid)

• Non‑selective MAO inhibitors: risk hypertensive crisis.
• Antipsychotics (e.g., haloperidol): reduce dopaminergic efficacy.
• Iron or calcium supplements: decrease levodopa absorption.

Moderate Interactions (Monitor Closely)

• Selective MAO‑B inhibitors (e.g., selegiline): may increase levodopa levels.
• Antihypertensive agents: may enhance orthostatic hypotension.
• High‑protein meals: may reduce drug bioavailability.