Melatonin Unimedic Pharma (Melatonin)

• Melatonin acts on melatonin receptors to help regulate sleep‑wake cycles.
• Primary insomnia: assists in reducing sleep latency and improving overall sleep quality in adults.
• Delayed sleep phase disorder: helps advance circadian timing to enable earlier sleep onset.
• Jet lag: facilitates adaptation to new time zones by normalizing the internal clock.
• Shift‑work sleep disorder: supports alignment of sleep patterns with atypical work schedules.
• Circadian rhythm disorder: aids in stabilising irregular sleep‑wake patterns caused by environmental or physiological factors.

• Melatonin binds to MT1 and MT2 receptors in the suprachiasmatic nucleus, mimicking endogenous melatonin. Activation of these G‑protein‑coupled receptors reduces neuronal firing during the night, signaling darkness and promoting the initiation of sleep. By modulating the circadian clock, the drug helps synchronize internal rhythms with external light‑dark cycles, facilitating sleep onset. The effect is dose‑dependent and does not involve direct sedation.

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

Common Side Effects

• Headache: mild to moderate headache that usually resolves without treatment.
• Dizziness: transient light‑headedness or vertigo, often occurring shortly after ingestion.
• Daytime sleepiness: feeling unusually drowsy during normal waking hours, which may affect alertness.
• Nausea: occasional stomach upset or queasiness, generally mild.

Serious or Rare Side Effects

• Allergic reaction: rash, itching, swelling of the face or throat, or difficulty breathing indicating possible anaphylaxis.
• Mood changes: emergence of depression, anxiety, or agitation, particularly in individuals with pre‑existing psychiatric conditions.
• Hormonal effects: possible alterations in reproductive hormone levels, which may affect menstrual cycles or fertility.

When using melatonin, certain precautionary measures should be observed to ensure safety.

• Pregnancy: safety not established; use only if clearly needed after risk assessment.
• Breastfeeding: insufficient data; consider potential exposure to the infant.
• Concomitant CNS depressants: may increase sedation and impair alertness.
• Elderly patients: start with a low dose due to increased sensitivity to sleepiness.
• Underlying medical conditions: assess liver or kidney impairment before initiating therapy.
• Store at ambient temperature: keep in the original container, protect from moisture and direct sunlight.

Melatonin can interact with other medicines; awareness of the interaction level guides safe use.

Major Interactions (Avoid)

• Anticoagulants: may increase bleeding risk.
• Immunosuppressants: possible reduction in therapeutic efficacy.
• CYP1A2 inhibitors: may raise melatonin plasma concentrations.
• Sedatives or hypnotics: additive central nervous system depression.
• Oral contraceptives: may alter hormone metabolism and effectiveness.

Moderate Interactions (Monitor Closely)

• Antidepressants (SSRIs, MAOIs): monitor for signs of serotonin syndrome.
• Antihypertensives: may enhance blood‑pressure‑lowering effects, requiring observation.