Last reviewed 2026-04-23 · How we verify

N-acetyl-5-methoxytryptamine

N-acetyl-5-methoxytryptamine (melatonin) acts as a melatonin receptor agonist to regulate circadian rhythms and provide antioxidant and anti-inflammatory effects.

N-acetyl-5-methoxytryptamine (melatonin) acts as a melatonin receptor agonist to regulate circadian rhythms and provide antioxidant and anti-inflammatory effects. Used for Circadian rhythm sleep disorders, Insomnia.

At a glance

Mechanism of action

This compound is a derivative of melatonin, the endogenous hormone produced by the pineal gland that regulates sleep-wake cycles. It binds to melatonin receptors (MT1 and MT2) in the suprachiasmatic nucleus and peripheral tissues, restoring circadian rhythm function. Additionally, it exerts direct free radical scavenging and mitochondrial antioxidant properties independent of receptor binding.

Approved indications

• Circadian rhythm sleep disorders
• Insomnia

Common side effects

• Headache
• Dizziness
• Somnolence
• Fatigue

Key clinical trials

• Effect of 1% Melatonin Gel Versus Calcium Hydroxide as an Intracanal Medicament on the Intensity of Postoperative Pain, Bacterial Load Reduction and Periapical MMP-9 Levels in Patients With Necrotic Pulp. (NA)
• A Study of Melatonin Concentration During Lactation
• Melatonin for Treatment of Delirium in Critically Ill Adult Patients (PHASE2)
• PICU-related Sleep and Circadian Dysregulation Pilot Study (NA)
• Studying Melatonin and Recovery in Teens (NA)
• Effect of Esketamine on Postoperative Sleep in Postmenopausal Women (NA)
• The Effect of Dexmedetomidine Infusion Alone Versus the Combination of Dexmedetomidine and Melatonin on Reduction of Post-operative Delirium (POD) After Open Brain Surgeries (PHASE4)
• Melatonin Versus Placebo for Bipolar Disorder (PHASE2)

Primary sources

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