Levodopa / Carbidopa Forte

What it is and how it works

Levodopa is converted to dopamine in the brain, replenishing striatal dopamine in Parkinson’s disease. Carbidopa inhibits peripheral dopa decarboxylase without crossing the blood–brain barrier, increasing the amount of levodopa reaching the brain and reducing peripheral adverse effects. The ‘forte’ strength contains a higher levodopa content per tablet (e.g. levodopa 250 mg / carbidopa 25 mg).

Indications

Parkinson’s disease and parkinsonian syndromes (excluding drug-induced parkinsonism).

Dosage and administration (summary)

Oral: dose individualised and titrated gradually according to response; the higher-strength tablet is generally used for maintenance in patients already stabilised on lower strengths, given in divided doses (e.g. three to four times daily). A total daily carbidopa dose of at least 70–100 mg is required for adequate decarboxylase inhibition.

Contraindications

Concomitant non-selective MAO inhibitors (stop at least 2 weeks before); angle-closure glaucoma; history of melanoma or suspicious undiagnosed skin lesions; severe psychosis; hypersensitivity to components.

Warnings and precautions

Dyskinesias, motor fluctuations, nausea, orthostatic hypotension, hallucinations, excessive daytime sleepiness and sudden sleep onset may occur. Monitor for impulse-control disorders and dopamine dysregulation syndrome. Avoid abrupt withdrawal (risk of neuroleptic malignant-like syndrome); high-protein meals may reduce efficacy; use with caution in cardiovascular, pulmonary or peptic ulcer disease.

Pregnancy

Avoid in pregnancy unless the benefit clearly outweighs the risk.

Storage and supply

Store below 25 °C, protected from light and moisture.

Source: reference summary prepared from the EU SmPC/EPAR, BNF and WHO Model Formulary. The approved product information in Iran governs.