Motilium Instant (Domperidone)

Domperidone acts on peripheral dopamine D2 receptors to enhance gastrointestinal motility, making it useful in several gastrointestinal disorders.

• Nausea and vomiting: reduces episodes and associated discomfort in patients with acute or chemotherapy‑induced nausea.
• Gastroparesis: accelerates gastric emptying and improves related symptoms such as early satiety and bloating.
• Functional dyspepsia: lessens upper abdominal pain, fullness, and post‑prandial discomfort.

• Domperidone blocks peripheral dopamine D2 receptors located in the chemoreceptor trigger zone and gastrointestinal smooth muscle. This antagonism removes dopamine‑mediated inhibition of gastrointestinal motility, thereby increasing the rate of gastric emptying and enhancing coordinated peristalsis without crossing the blood‑brain barrier.

Domperidone may cause a range of adverse reactions, which are categorized by frequency and clinical significance.

Common Side Effects

• Dry mouth
• Headache
• Abdominal cramps
• Dizziness
• Diarrhea
• Constipation

Serious or Rare Side Effects

• QT interval prolongation and cardiac arrhythmias
• Severe allergic reactions such as anaphylaxis or rash
• Extrapyramidal symptoms including tremor or Parkinsonism
• Hyperprolactinemia with galactorrhea
• Neuroleptic malignant syndrome
• Hepatic dysfunction

When prescribing domperidone, clinicians should consider several safety measures to minimize risk.

• Cardiac risk assessment: evaluate history of arrhythmia or prolonged QT interval.
• Electrolyte monitoring: check potassium and magnesium levels before and during therapy.
• Hepatic impairment: use with caution in patients with liver dysfunction.
• CYP3A4 inhibitors: avoid concomitant use with strong inhibitors that may raise plasma levels.
• Duration of therapy: limit to the shortest effective period.
• Store at ambient temperature: keep in the original pack, protect from moisture.

Domperidone can interact with other medicines, altering its efficacy or safety profile.

Major Interactions (Avoid)

• Strong CYP3A4 inhibitors (e.g., ketoconazole, itraconazole) may increase domperidone concentrations.
• Macrolide antibiotics such as erythromycin or clarithromycin can raise plasma levels and risk QT prolongation.
• Other QT‑prolonging agents (e.g., quinidine, sotalol) may synergistically increase cardiac risk.

Moderate Interactions (Monitor Closely):\n- Anticholinergic drugs (e.g., atropine) may diminish the prokinetic effect.

• Co‑administration with other prokinetics or antiemetics (e.g., metoclopramide) may raise the likelihood of extrapyramidal symptoms.