melatonin (generic name)

a nutraceutical product - treats Insomnia, Insomnia in the elderly, REM sleep behavior disorder, Parkinson's disease, Exercise performance, Alz...
Table of Contents
powered by healthline

Average Ratings

Interactions

Interactions with Drugs

Melatonin is broken down (metabolized) in the body by liver enzymes. As a result, drugs that alter the activity of these enzymes may increase or decrease the effects of melatonin supplements.

Increased daytime drowsiness is reported when melatonin is used at the same time as the prescription sleep-aid zolpidem (Ambien®), although it is not clear that effects are greater than with the use of zolpidem alone. In theory, melatonin may increase the amount of drowsiness caused by some other drugs, for example benzodiazepines such as lorazepam (Ativan®) or diazepam (Valium®), barbiturates such as phenobarbital, narcotics such as codeine, some antidepressants, and alcohol. Caution is advised while driving or operating machinery.

Based on preliminary evidence, melatonin should be avoided in patients taking the blood-thinning medication warfarin (Coumadin®) and possibly in patients using other blood-thinners (anticoagulants) such as aspirin or heparin.

Multiple drugs are reported to lower natural levels of melatonin in the body. It is not clear that there are any health hazards of lowered melatonin levels or if replacing melatonin with supplements is beneficial. Examples of drugs that may reduce production or secretion of melatonin include non-steroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen (Motrin®, Advil®) or naproxen (Naprosyn®, Aleve®); beta-blocker blood pressure medications such as atenolol (Tenormin®) or metoprolol (Lopressor®, Toprol®); and medications that reduce levels of vitamin B6 in the body (such as birth control pills, hormone replacement therapy, loop diuretics, hydralazine, or theophylline). Other agents that may alter synthesis or release of melatonin include diazepam, vitamin B12, verapamil, temazepam, and somatostatin.

Based on preliminary evidence, melatonin should be avoided in patients taking anti-seizure medications. It has been suggested that melatonin may lower seizure threshold and increase the risk of seizure. However, multiple other studies actually report reduced incidence of seizure with regular melatonin use. This remains an area of controversy. Additionally, carbamazepine and valproate may alter melatonin levels and should be used with caution. Patients with seizure disorders taking melatonin should be monitored closely by a healthcare professional.

Melatonin may increase or decrease blood pressure; study results conflict. Therefore, it may interact with heart or blood pressure medications making close monitoring necessary.

It is not clear if caffeine alters the effects of melatonin supplements in humans. Caffeine is reported to raise natural melatonin levels in the body, possibly due to effects on liver enzymes. However, caffeine may also alter circadian rhythms in the body, with effects on melatonin secretion.

Elevated blood sugar levels (hyperglycemia) have been reported in patients with type 1 diabetes (insulin-dependent diabetes) and low doses of melatonin have reduced glucose tolerance and insulin sensitivity. Caution is advised in patients taking drugs for diabetes by mouth or insulin. Serum glucose levels may need to be monitored by a healthcare provider, and medication adjustments may be necessary.

Alcohol consumption seems to affect melatonin secretion at night.

Preliminary reports suggest that melatonin may aid in reversing symptoms of tardive dyskinesia associated with haloperidol (tranquilizer) use.

Based on preliminary evidence, melatonin may increase the effects of isoniazid against Mycobacterium tuberculosis.

Based on animal research, melatonin may increase the adverse effects of methamphetamine on the nervous system.

Based on laboratory study, melatonin may increase the neuromuscular blocking effect of the muscle relaxant succinylcholine, but not vecuronium.

Melatonin premedication may decrease the doses of propofol and thiopental required to induce anesthesia.

Interactions with Herbs and Dietary Supplements

Melatonin may increase daytime sleepiness or sedation when taken with herbs or supplements that may cause drowsiness.

Elevated blood sugar levels (hyperglycemia) have been reported in patients with type 1 diabetes (insulin-dependent diabetes), and low doses of melatonin have reduced glucose tolerance and insulin sensitivity. Caution is advised when using herbs or supplements that may also raise blood sugar levels, such as arginine, cocoa, DHEA, and ephedra (when combined with caffeine).

Based on preliminary evidence of an interaction with the blood thinning drug warfarin, and isolated reports of minor bleeding, melatonin may increase the risk of bleeding when taken with herbs and supplements that are believed to increase the risk of bleeding.

It is not clear if caffeine alters the effects of melatonin supplements in humans. Caffeine is reported to raise natural melatonin levels in the body, possibly due to effects on liver enzymes. However, caffeine may also alter circadian rhythms in the body, with effects on melatonin secretion.

Chasteberry (Vitex agnus-castus) may increase natural secretion of melatonin in the body, based on preliminary research.

In animal study, DHEA and melatonin have been noted to stimulate immune function, with slight additive effects when used together. Effects of this combination in humans are not clear.

Based on animal study, a combination of echinacea and melatonin may reduce immune function. Effects of this combination in humans are not clear.

Severe folate deficiency may reduce the body's natural levels of melatonin, based on preliminary study.

Page: < Back 1 2 3 4 Next >
Licensed from
Top of page
General Drug Tools
General Drug Tools view all tools
Tools for
Healthy Living
Tools for Healthy Living view all tools
Search Tools
Search Tools view all tools
Insurance Plan Tools
Insurance Plan Tools view all tools