Melatonina Pharma Nord (Melatonin)

Melatonin acts on the melatonin receptor system to regulate the sleep‑wake cycle.

• Insomnia: helps reduce sleep onset latency and improve overall sleep quality in adults.
• Circadian rhythm sleep disorders: assists in realigning disrupted internal clocks, facilitating more regular sleep patterns.
• Jet lag: shortens the adjustment period after rapid time‑zone travel, promoting faster restoration of normal sleep timing.

• Melatonin binds as an agonist to MT1 and MT2 receptors located in the suprachiasmatic nucleus of the hypothalamus. Activation of these G‑protein‑coupled receptors modulates intracellular cyclic AMP levels, leading to phase‑shifting of the circadian pacemaker and promoting the physiological transition to sleep. By mimicking the endogenous hormone surge at night, melatonin reinforces the night‑time signal that prepares the body for rest.

Melatonin is generally well tolerated, but some users may experience adverse reactions.

Common Side Effects

• Headache: mild throbbing pain occurring within an hour after ingestion.
• Dizziness: transient light‑headedness or unsteadiness, often after the first dose.
• Daytime sleepiness: feeling unusually drowsy during normal waking periods.
• Nausea: mild stomach upset or queasiness that usually resolves spontaneously.

Serious or Rare Side Effects

• Allergic reaction: rash, itching, facial swelling or breathing difficulty indicating hypersensitivity.
• Mood changes: new or worsening depression or anxiety that should be reported.
• Severe hypotension: notable blood pressure drop causing faintness or syncope.
• Seizures: rare convulsive episodes requiring immediate medical care.

These effects are reported in clinical use. Patients should monitor for any changes.

When using melatonin, certain precautions should be observed to ensure safe and effective therapy.

• Assess sleep pattern: evaluate baseline sleep habits before initiating therapy.
• Avoid use with shift work: melatonin may be less effective for individuals working irregular hours.
• Monitor in depression: patients with depressive disorders should be observed for mood changes.
• Use caution in elderly: start with the lowest effective dose due to increased sensitivity.
• Review medication list: check for potential interactions with anticoagulants or CNS depressants.
• Pregnancy considerations: discuss risks with a healthcare provider before use.
• Store at room temperature: keep in the original container, protect from moisture and direct sunlight.

Melatonin can interact with several medicines; awareness of major and moderate interactions helps manage safety.

Major Interactions (Avoid)

• Warfarin: melatonin may increase the anticoagulant effect, raising the risk of bleeding especially at higher doses.
• Cyclosporine: co‑administration can raise cyclosporine blood levels, potentially leading to nephrotoxicity.
• Fluvoxamine (CYP1A2 inhibitor): strong inhibition can markedly increase melatonin plasma concentrations, enhancing its pharmacologic effects.

Moderate Interactions (Monitor Closely)

• Benzodiazepines: combined use may produce additive sedation, requiring dose adjustment of either agent.
• Antihypertensives: melatonin may augment the blood‑pressure‑lowering action, possibly causing hypotension.
• Oral contraceptives: hormonal agents can modify melatonin metabolism, potentially affecting its efficacy.