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

Contraindication/Precautions

Contraindicated in:

• Hypersensitivity;
• Pregnancy and lactation.

Use Cautiously in:

• Seizure disorders;
• Diabetes;
• Hypertension.

Adverse Reactions/Side Effects

CV: hypotension

CNS: drowsiness, headache, dizziness

GI: nausea, vomiting, abdominal cramps

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

Interactions

Natural Drug Interaction

• Additive sedation with CNS depressants..
• May increase 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:
Tablets: 3 mg

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.

Potential Diagnoses

• Insomnia (Indications)

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.