Interactions

Interactions with Drugs

Note: This section discusses both melatonin in the body and melatonin from other sources, and the effects of other agents on melatonin and when taken with melatonin. Many drugs may lower natural melatonin levels in the body. These include nonsteroidal anti-inflammatory drugs (NSAIDs, including ibuprofen [Motrin®, Advil®] or naproxen [Naprosyn®, Aleve®]), beta-blocker blood pressure medications (including propranolol [Inderal®], atenolol [Tenormin®], and metoprolol [Lopressor®, Toprol®]), and agents that lower levels of vitamin B6 in the body (including birth control, hormone replacement therapy, loop diuretics, hydralazine, and theophylline). Other agents that may affect melatonin levels include caffeine, diazepam, estradiol, somatostatin, temazepam, verapamil, and vitamin B12.

Melatonin may affect the risk of clotting. Caution is advised in people with bleeding or clotting disorders and those taking drugs that may affect bleeding or clotting. Dosing adjustments may be necessary.

Melatonin may affect blood sugar levels. Caution is advised when using medications that may also affect blood sugar. People taking drugs for diabetes by mouth or insulin should be monitored closely by a qualified healthcare professional, including a pharmacist. Medication adjustments may be necessary.

Melatonin may affect blood pressure. Caution is advised in people taking drugs that affect blood pressure.

Melatonin may interfere with the way the body processes certain drugs using the liver's cytochrome P450 enzyme system. As a result, the levels of these drugs may be altered in the blood and may cause altered effects or potentially serious adverse reactions. People using any medications should check the package insert and speak with a qualified healthcare professional, including a pharmacist, about possible interactions.

Melatonin may increase the amount of drowsiness caused by some drugs. Examples include 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.

Melatonin may also interact with ACE inhibitors, agents passed by the kidneys, agents that affect blood vessel width, agents that affect GABA, agents that affect the immune system, agents that affect the nervous system, agents that harm the liver, agents that increase seizure risk, agents that increase urine flow, agents that protect against radiation, agents that regulate body temperature, agents that treat Parkinson's disease, agents that treat seizures, alcohol, Alzheimer's agents, anesthetics, antiaging agents, antiarthritis agents, antiasthma agents, anticancer agents, anti-inflammatory agents, antiparasite agents, antipsychotic agents, antiulcer agents, antivirals, anxiety agents, birth control, caffeine, calcium channel blockers, cholesterol-lowering agents, cognitive agents, dental agents, dextromethorphan, ear agents, epithalamin, estrogens, exercise performance agents, eye agents, fertility agents, flumazenil, genital and urinary disorder agents, glaucoma agents, headache agents, heart agents, heart rate-regulating agents, hormonal agents, isoniazid, lithium, lung agents, magnetic fields, methamphetamines, methoxamine, musculoskeletal agents, neuromuscular blockers, opioids, osteoporosis agents, pain relievers, remifentanil, sevoflurane, skin agents, stomach agents, tacrine, thyroid hormones, vaccines, valproic acid, and weight loss agents.

Interactions with Herbs and Dietary Supplements

Note: This section discusses both melatonin in the body and melatonin from other sources, and the effects of other agents on melatonin and when taken with melatonin. Many drugs may lower natural melatonin levels in the body. These include nonsteroidal anti-inflammatory drugs (NSAIDs, including ibuprofen [Motrin®, Advil®] or naproxen [Naprosyn®, Aleve®]), beta-blocker blood pressure medications (including propranolol [Inderal®], atenolol [Tenormin®], and metoprolol [Lopressor®, Toprol®]), and agents that lower levels of vitamin B6 in the body (including birth control, hormone replacement therapy, loop diuretics, hydralazine, and theophylline). Other agents that may affect melatonin levels include caffeine, diazepam, estradiol, somatostatin, temazepam, verapamil, and vitamin B12.

Melatonin may affect the risk of clotting. Caution is advised in people with bleeding or clotting disorders and those taking herbs and supplements that may affect bleeding or clotting. Dosing adjustments may be necessary.

Melatonin may affect blood sugar levels. Caution is advised when using herbs or supplements that may also affect blood sugar. Blood glucose levels may require monitoring, and doses may need adjustment.

Melatonin may affect blood pressure. Caution is advised in people taking herbs or supplements that affect blood pressure.

Melatonin may interfere with the way the body processes certain herbs or supplements using the liver's cytochrome P450 enzyme system. As a result, the levels of other herbs or supplements may alter in the blood. It may also alter the effects that other herbs or supplements possibly have on the cytochrome P450 system.

Melatonin may increase the amount of drowsiness caused by some herbs or supplements.

Melatonin may also interact with 5-HTP, ACE inhibitors, Alzheimer's herbs and supplements, anesthetics, antiaging herbs and supplements, antiarthritis herbs and supplements, antiasthma herbs and supplements, anticancer herbs and supplements, antidepressants, anti-inflammatory herbs and supplements, antioxidants, antiparasite herbs and supplements, antipsychotic herbs and supplements, antiulcer herbs and supplements, antivirals, anxiety herbs and supplements, birth control, caffeine-containing herbs and supplements, chasteberry, cholesterol-lowering herbs and supplements, cognitive herbs and supplements, dental herbs and supplements, DHEA, ear herbs and supplements, echinacea, exercise performance herbs and supplements, eye herbs and supplements, fertility herbs and supplements, folate, GABA, genital and urinary disorder herbs and supplements, glaucoma herbs and supplements, headache herbs and supplements, heart herbs and supplements, heart rate-regulating herbs and supplements, herbs and supplements passed by the kidneys, herbs and supplements that affect blood vessel width, herbs and supplements that affect GABA, herbs and supplements that affect the immune system, herbs and supplements that affect the nervous system, herbs and supplements that increase seizure risk, herbs and supplements that increase urine flow, herbs and supplements that protect against radiation, herbs and supplements that regulate body temperature, herbs and supplements that treat Parkinson's disease, herbs and supplements that treat seizures, hormonal herbs and supplements, light therapy, lithium, liver herbs and supplements, lung herbs and supplements, magnetic fields, meditation, musculoskeletal herbs and supplements, music therapy, neuromuscular blockers, osteoporosis herbs and supplements, pain relievers, phytoestrogens, skin herbs and supplements, stomach herbs and supplements, thyroid hormones, and weight loss herbs and supplements.

This evidence-based monograph was prepared by The Natural Standard Research Collaboration

www.naturalstandard.com