melatonin

General

Complementary/Alternative Medicine: This monograph describes a natural or herbal product that is not subject to FDA guidelines for medicines. Patients and clinicians are advised to read package labels carefully to ensure safe and efficacious use.

Pronunciation:
mel-uh-toh-nin


Trade Name(s)

  • pineal hormone
  • N-acetyl-5–methoxtryptamine

Ther. Class.

sedative/hypnotics

Common Uses

Sleep disorders (including insomnia, jet lag and circadian rhythm disorders)

Action

Melatonin is a hormone secreted from the pineal gland in a 24-hour circadian rhythm, regulating the normal sleep/wake cycle. As a supplement, melatonin has both phase-shifting and sleep-promoting properties. In addition to promoting sleep, physiologic roles of melatonin include regulation of the secretion of growth hormone and gonadotropic hormones. It also possesses antioxidant activity.

Therapeutic Effect(s):

Improved sleep pattern.

Pharmacokinetics

Absorption: Unknown

Distribution: Unknown

Metabolism and Excretion: Unknown

Half-life: Unknown

TIME/ACTION PROFILE

ONSETPEAKDURATION
POunknownunknownunknown

Contraindication/Precautions

Contraindicated in:

  • Hypersensitivity;
  • Pregnancy and lactation.

Use Cautiously in:

  • Seizure disorders;
  • Diabetes;
  • Hypertension.

Adverse Reactions/Side Effects

CV: hypotension

GI: abdominal cramps, nausea, vomiting

Neuro: dizziness, drowsiness, headache

* CAPITALS indicate life-threatening.
Underline indicate most frequent.

Interactions

Natural Drug Interaction

  • Additive sedation with  CNS depressants. 
  • May ↑ bleeding risk with  antiplatelet agents and  anticoagulants. 
  • May interfere with the glucose-lowering effects of  hypoglycemic agents. 
  • May decrease effectiveness of nifedipine. 

Natural-Natural:

  • May have additive sedative effects with herbs that have sedative properties including 5–HTP, kava, St.John's wort, valerian and others.
  • May increase risk of bleeding with herbs that have antiplatelet/anticoagulant properties such as clove,  garlic, ginger, gingko, ginseng and others.

Route/Dosage

PO (Adults): 0.3–10 mg daily at bedtime.

Availability

Capsules: OTC

Tablets: OTC

Sublingual Tablets: OTC

Gummies: OTC

Assessment

  • Assess sleep patterns before and periodically throughout therapy.

Lab Test Considerations:

Monitor blood glucose, coagulation panel, hormone panel, and lipid panel periodically during therapy.

Implementation

  • PO Administer before bedtime.

Patient/Family Teaching

  • Instruct patient to take at bedtime as directed.
  • Causes drowsiness. Caution patient to avoid driving and other activities requiring alertness until response to medication is known.
  • Caution patient to avoid concurrent use of alcohol or other CNS depressants.
  • Advise female patient to notify health care professional if pregnancy is planned or suspected or if breastfeeding.

Evaluation/Desired Outcomes

Relief of insomnia.