Melanoc Pr (Melatonin)

Melanoc Pr (melatonin) is a hormone analogue used to address disorders of the sleep‑wake cycle by influencing circadian rhythm regulation.

• Insomnia: helps reduce sleep onset latency and improve overall sleep quality in adults.
• Delayed sleep phase disorder: advances circadian timing to facilitate earlier sleep onset.
• Jet lag: assists in re‑synchronizing the internal clock after rapid time‑zone travel.
• Shift work disorder: supports adaptation to irregular work schedules by promoting sleep during desired periods.
• Non‑24‑hour sleep‑wake rhythm disorder: aids in establishing a regular 24‑hour sleep pattern in individuals with circadian rhythm dysfunction.

• Melatonin binds to MT1 and MT2 receptors in the suprachiasmatic nucleus of the hypothalamus, activating G‑protein‑coupled pathways that reduce cyclic AMP levels. This receptor activation phase‑shifts the circadian pacemaker, aligning the internal biological clock with the external light‑dark cycle and facilitating the initiation of sleep.

Melatonin is generally well tolerated, but several adverse reactions have been reported.

Common Side Effects

• Drowsiness: excessive sleepiness that may affect daytime activities.
• Headache: mild to moderate head pain occurring after ingestion.
• Dizziness: transient light‑headed sensation, especially when standing quickly.
• Gastrointestinal discomfort: nausea, abdominal cramps or mild upset stomach.

Serious or Rare Side Effects

• Allergic reaction: rash, itching, swelling of face or throat, or anaphylaxis requiring immediate medical attention.
• Mood changes: emergence or worsening of depression, anxiety, or irritability.
• Hormonal effects: irregular menstrual periods or changes in libido in some women.

When considering melatonin therapy, several safety considerations should be reviewed.

• Contraindications: avoid use in individuals with known hypersensitivity to melatonin.
• Pregnancy: limited data; use only if potential benefit justifies potential risk.
• Breastfeeding: caution advised as melatonin may be secreted in breast milk.
• Drug interactions: review concomitant medications that may affect melatonin metabolism.
• Underlying conditions: assess for depression, seizure disorders, or autoimmune disease before initiating.
• Store at ambient temperature: keep below 25 °C, in the original container, protected from moisture and light.

Melatonin can interact with several medicines, altering its efficacy or safety profile.

Major Interactions (Avoid)

• Anticoagulants: may increase bleeding risk when combined with warfarin or similar agents.
• Immunosuppressants: potential reduction of immunosuppressive effect, especially with cyclosporine.

Moderate Interactions (Monitor Closely)

• CNS depressants: additive sedative effect with benzodiazepines, barbiturates, or alcohol.
• CYP1A2 inhibitors: fluvoxamine and ciprofloxacin can raise melatonin plasma levels.
• Hormonal contraceptives: may alter melatonin metabolism, requiring monitoring.
• Antidepressants: SSRIs and SNRIs may affect sleep patterns when used together.