Madopar

Antiparkinsonian Drug

Drug class: Dopaminergic Antiparkinsonian Agent

Levodopa and Benserazide (MADOPAR)（中文：美多芭）

Pronunciation

Madopar 250mg

Common Strengths of Madopar

• Capsules:
  • 62.5 mg (12.5 mg benserazide and 50 mg levodopa)
  • 125 mg (25 mg benserazide and 100 mg levodopa)
  • 250 mg (50 mg benserazide and 200 mg levodopa)
• Modified-release capsules (HBS): 125 mg (25 mg benserazide and 100 mg levodopa)
• Dispersible tablet: 125 mg (25 mg benserazide and 100 mg levodopa)

Drug Trade Names

• Madopar
• Madopar HBS (Hydrodynamically Balanced System)
• Madopar Rapid (Dispersible tablets)

Drug Usage

Madopar is used to treat symptoms of Parkinson's disease, including tremors, stiffness, and diffculty with movement. It dose not cure the disease but helps manage its symptoms.

Mechanism of Action

Madopar combines two active ingredients: levoopa and benserazide.

Levodopa is converted into dopamine in the brain, which alleviates symptoms caused by dopamine deficiency in Parkinson's patients. Benserazide prevents levodopa from converting to dopamine outside the brain, thus enhancing its effecacy and minimizing side effects.

Route of Administration

Madopar is administered orally in the form of capsules or dispersible tablets.

Dosage

Initial dose typically start at Madopar 62.5 mg (12.5 mg benserazide/50 mg levodopa) three to four times daily; dose are adjusted based on response.

Side Effects

Frequency	Adverse reactions
Common Side Effects	Nausea
	Vomiting
	Dizziness
	Sleep disturbances
Serious Side Effects	Hallucinations
	Uncontrolled movements
	Severe allergic reactions

Pharmacokinetics

Madopar's onset time can vary; Immediate-release forms may take effect within 30 mintures, while modified-release forms may take longer. The duration of action can last several hours depending on the formulation used.

Drug Precautions

Pregnancy

Use during pregnancy should be carefully considered; consult a healthcare provider.

Breastfeeding

Caution is advised as both active ingredients can pass into breast milk.

Drug Monitoring Items

• Blood Cell Count: as Madopar can cause decreases in blood cell counts, including haemolytic anemia, thrombocytopenia, and leukopenia.
• Hepatic and Renal Function: Periodic assessments of liver and kidney function are recommended to detect any adverse effects early.
• Cardiovascular Monitoring: Patients on antihypertensive medications should monitor blood pressure, especially when initiating therapy or adjusting doses.
• Neurological Assessment: Monitoring for neuroleptic malignant-like syndrome is crucial, particularly if there are symptoms such as hyperpyrexia or muscular rigidity following abrupt withdrawal of the medication.
• Psychiatric Evaluation: Patients should be assessed for mental health changes, including paranoia, depression, and hallucinations, which can occur with Madopar use.
• Motor Function Evaluation: Regular assessments of motor symptoms and dyskinesias are important to adjust dosages effectively and manage any fluctuations in drug efficacy.
• Dosage Adjustments: Individualized dosing is critical; it may take several weeks to determine the optimal dose for symptom control without significant side effects.
• Lifestyle Adjustments: Patients should be advised on the gradual resumption of activites post-treatment initiation to minimize injury risks associated with sudden movements or changes in muscle control.

Drug Interactions

Madopar can interact with several medications, including:

• Non-Selective Monoamine Oxidase Inhibitors (MAOIs):
  • Madopar should not be taken with non-selective MAO inhibitors (e.g. tranylcypromine, phenelzine) due to the risk of hypertensive crisis. An interval of at least two weeks should be observed between stopping a non-selective MAOI and starting Madopar therapy.
• Sympathomimetics:
  • Concomitant use of sympathomimetic agents (e.g. epinephrine, norepinephrine) is contraindicated as levodopa may potentiate their effects, necessitating close cardiovascular monitoring if co-administration is unavoidable.
• Neuroleptics:
  • Antipsychotics with dopamine receptor-blocking proprties can antagonize the effects of Madopar, potentially worsening Parkinsonian symptoms.
• Iron Supplements:
  • Ferrous sulfate can reduce absorption and may diminish the effectiveness of Madopar
• Antacids:
  • Antacids can interfere with the absorption of levodopa when taken concurrently with Madopar HBS formulations, reducing its bioavailability, and so should not be taken at the same time.
• Metoclopramide:
  • This medication may increase the rate of levodopa absorption, potentially enhancing the effects of Madopar.
• Domperidone:
  • Domperidone can increase the bioavailability of levodopa by stimulating gastric emptying, which may improve therapeutic oitcomes when used alongside Madopar.

FAQ

How Should I Take the Tablet?

Take Madopar on an empty stomach or with low-protein food if necessary; avoid high-protein meals that can reduce absorption.

What Should I Avoid While Taking?

Avoid taking iron supplements within two hours of Madopar and high-protein meals that may interfere with its effectiveness.

What Happens if I Miss a Dose?

If you miss a dose, take it as soon as you remember unless it is close to the time for your next dose; do not double up on doses.