Melatonin Teva (Melatonin)

• Melatonin acts on the melatonin receptor pathway to address sleep‑related disorders.
• Insomnia: helps reduce sleep latency and improve sleep maintenance in adults.
• Jet lag: assists in re‑synchronizing the internal clock after rapid time‑zone travel.
• Circadian rhythm sleep disorder: supports normalization of disrupted sleep‑wake cycles.
• Shift work disorder: facilitates adaptation to irregular work hours.
• Delayed sleep phase syndrome: promotes earlier sleep onset.
• Advanced sleep phase syndrome: aids in delaying sleep onset.

• Melatonin binds to MT1 and MT2 receptors in the suprachiasmatic nucleus of the hypothalamus, mimicking the endogenous hormone released by the pineal gland during darkness. Activation of these G‑protein‑coupled receptors modulates intracellular cyclic AMP levels, leading to phase‑shifting of the circadian pacemaker and promoting the physiological processes that initiate sleep. The resultant signal cascade also influences downstream neurotransmitters such as GABA and serotonin, further facilitating the transition to sleep.

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

Common Side Effects

• Headache: mild to moderate intensity, often resolving without intervention.
• Dizziness: sensation of light‑headedness, typically brief.
• Daytime sleepiness: feeling unusually drowsy during waking hours, especially if taken late at night.
• Nausea: mild gastrointestinal discomfort that usually subsides.
• Vivid dreams: unusually intense or memorable dreaming episodes.

Serious or Rare Side Effects

• Allergic reaction: rash, itching, swelling, or difficulty breathing requiring immediate medical attention.
• Severe skin eruption: conditions such as Stevens‑Johnson syndrome or toxic epidermal necrolysis.
• Mood changes: emergence of depression, anxiety, or suicidal thoughts.
• Seizures: rare occurrence of convulsive episodes, particularly in predisposed individuals.

• When considering melatonin therapy, several precautionary measures should be observed to ensure safe use.
• Assess underlying sleep disorder: confirm diagnosis before initiating therapy.
• Avoid operating machinery: potential daytime drowsiness may impair performance.
• Caution with antidepressants: concurrent use may alter melatonin metabolism.
• Not recommended for children without medical supervision: pediatric safety data are limited.
• Limit alcohol consumption: alcohol can enhance sedative effects.
• Store at ambient temperature: keep in original container, protect from moisture and direct sunlight.

Melatonin can interact with other medicines, affecting its efficacy or safety profile.

Major Interactions (Avoid)

• CNS depressants (e.g., benzodiazepines, barbiturates): may cause excessive sedation.
• Anticoagulants (e.g., warfarin): potential increase in bleeding risk.
• Immunosuppressants (e.g., cyclosporine): may reduce drug effectiveness.

Moderate Interactions (Monitor Closely)

• Fluvoxamine and other CYP1A2 inhibitors: can raise melatonin plasma levels.
• Oral contraceptives: may alter hormone balance and melatonin metabolism.
• NSAIDs: concurrent use may increase risk of gastrointestinal discomfort.
• Antihypertensives: melatonin may have additive blood‑pressure‑lowering effects.