Mecastrin (Melatonin)

Mecastrin is a melatonin receptor agonist that addresses disorders of the circadian rhythm and related sleep disturbances.

• Insomnia: helps reduce the time needed to fall asleep and may improve sleep quality.
• Jet lag: assists in adjusting the internal clock after rapid east‑west travel.
• Shift work disorder: supports sleep onset and maintenance for individuals working non‑standard hours.

• Melatonin in Mecastrin binds to MT1 and MT2 receptors in the suprachiasmatic nucleus, mimicking endogenous melatonin. This activation synchronises the circadian clock, promoting the onset of sleep and regulating the sleep‑wake cycle without directly inducing sedation.

Mecastrin may cause a range of adverse reactions, most of which are mild and transient.

Common Side Effects

• Headache: mild to moderate pain often resolving without intervention.
• Dizziness: sensation of light‑headedness, typically short‑lived.
• Daytime sleepiness: occasional residual drowsiness after dosing.
• Nausea: mild gastrointestinal discomfort.
• Vivid dreams: occasional alteration in dream patterns.

Serious or Rare Side Effects

• Hypersensitivity reactions: rash, itching, or swelling indicating an allergic response.
• Severe allergic reaction (anaphylaxis): rare but requires immediate medical attention.
• Serotonin syndrome: extremely rare when combined with serotonergic agents.
• Severe depression or mood changes: uncommon but reported.
• Hallucinations: rare neuropsychiatric effect.
• Persistent daytime fatigue: prolonged excessive sleepiness beyond expected duration.

When considering Mecastrin, several safety measures should be observed.

• Evaluate sleep hygiene: ensure non‑pharmacologic sleep practices are in place.
• Medical supervision: use under guidance of a healthcare professional.
• Pediatric use: avoid in children unless specifically prescribed.
• Anticoagulant caution: monitor for increased bleeding risk when combined with warfarin.
• Pregnancy and lactation: consult a physician as safety data are limited.
• Store at ambient temperature: keep in the original pack, protect from moisture and direct sunlight.

Mecastrin can interact with other medicines, requiring attention to potential additive effects.

Major Interactions (Avoid)

• Warfarin: may enhance anticoagulant effect, increasing bleeding risk.
• Cyclosporine: possible increase in melatonin levels, leading to heightened sedation.
• SSRIs or SNRIs: combined use may raise the risk of serotonin syndrome.

Moderate Interactions (Monitor Closely)

• Sedative agents (benzodiazepines, Z‑drugs): may intensify drowsiness.
• Antihypertensives: melatonin can modestly lower blood pressure.
• Hormonal contraceptives: may reduce contraceptive efficacy.
• Caffeine: may counteract melatonin’s sleep‑promoting action.
• Alcohol: can increase sedation and impair coordination.