Mosegor (Pizotifen)

Pizotifen is used in the prophylaxis of primary headache disorders and related conditions.

• Migraine prophylaxis: Decreases the frequency, intensity, and duration of migraine attacks in adults who experience recurrent episodes.
• Cluster headache prevention: Reduces the number of cluster headache bouts and may lessen associated autonomic symptoms.
• Allergic rhinitis: Provides relief from nasal congestion, sneezing, and itching caused by seasonal allergens.
• Seasonal allergic conjunctivitis: Helps control eye itching and redness related to pollen exposure.

• Pizotifen exerts its therapeutic effect by competitively antagonizing serotonin 5‑HT2 receptors and histamine H1 receptors in the central nervous system and peripheral tissues. Blockade of 5‑HT2 receptors limits neurogenic inflammation and vasodilation of cranial vessels, while H1 antagonism contributes to stabilization of mast cells and reduction of allergic mediators, together diminishing migraine and cluster headache triggers, thereby providing prophylactic benefit.

Pizotifen may be associated with a range of adverse reactions, most of which are mild and reversible.

Common Side Effects

• Drowsiness: Feeling of sleepiness or reduced alertness.
• Weight gain: Increase in body weight over time.
• Dry mouth: Reduced salivation leading to a dry oral cavity.
• Constipation: Decreased bowel movements or difficulty passing stool.
• Dizziness: Light‑headed sensation, especially when standing quickly.

Serious or Rare Side Effects

• Cardiac arrhythmia: Irregular heart rhythm that may require medical attention.
• Severe allergic reaction: Anaphylaxis or angioedema presenting with swelling and breathing difficulty.
• Hepatotoxicity: Signs of liver injury such as jaundice or elevated enzymes.
• Mood changes: Depression or suicidal thoughts in susceptible individuals.

When prescribing Pizotifen, clinicians should consider several precautionary measures to ensure patient safety.

• Assess medical history: Review cardiovascular, hepatic, and psychiatric conditions before initiating therapy.
• Monitor weight: Track body weight periodically as the drug can cause weight gain.
• Evaluate sedation: Caution patients about operating machinery or driving if drowsiness occurs.
• Review concomitant drugs: Check for other CNS depressants or antihistamines that may enhance sedation.
• Pregnancy and lactation: Use only if the potential benefit outweighs unknown risks, as safety data are limited.
• Store at ambient temperature: Keep below 25 °C in the original packaging, protected from moisture and light.

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

Major Interactions (Avoid)

• MAO inhibitors: Combined use may increase serotonergic effects and risk of hypertension.
• CYP2D6 inhibitors: May raise plasma levels of Pizotifen, enhancing adverse effects.

Moderate Interactions (Monitor Closely)

• CNS depressants: Additive sedation when used with alcohol, benzodiazepines, or opioids.
• Antihistamines: Overlapping H1 blockade can intensify drowsiness.
• Anticholinergic agents: May worsen dry mouth and constipation.