Melatonin adverse effects

Melatonin appears to be well tolerated and is often used in preference to over-the-counter "sleep-aid" drugs. Although melatonin is associated with few adverse effects, some next-day drowsiness has been reported as well as fatigue, dizziness, headache, and irritability. Melatonin may affect blood pressure as both increases and decreases in blood pressure have been observed. Careful monitoring is recommended, particularly in patients initiating melatonin therapy while taking antihypertensive medications. 

Acute exogenous administration of melatonin causes sedation, fatigue, self-reported vigor, confusion, and a reduction in body temperature in healthy subjects. The effects of chronic treatment have not been studied, and adverse effects have not been systematically reported. 

Retinal damage has been briefly reported as an adverse effect of melatonin (9). 

This is a warning against the uncontrolled use of apparently innocuous substances. The absence of adverse effects in healthy people taking melatonin for various reasons does not mean complete safety, particularly in people who are unwell. 

Melatonin can cause some adverse effects. People should contact their health care provider if they have difficulty sleeping or feel too sleepy, develop a headache, chills, or itching, feel confused, or have a fast pulse after taking melatonin. Individuals who will be undergoing surgery should tell the anesthesiologist that they have been taking melatonin. 

In rats, ototoxicity caused by gentamicin or tobramycin was amehorated by melatonin, which did not interfere with the antibiotic action of the aminoglycosides (70). The free radical scavenging agent alpha-lipoic acid has previously been shown to protect against the cochlear adverse effects of systemically administered aminoglycoside antibiotics, and in a recent animal study it also prevented cochlear toxicity after the administration of neomycin 5% directly to the round window membrane over 7 days (71). 

Describe the proposed medical uses and adverse effects of dehydroepiandrosterone and melatonin. 

Ramelteon, (S)-Al-[2-(l,6,7,8-tetrahydro-2H-indeno-[5,4-h]furan-8-yl)ethyl]propio-namide (TAK-375), has four times the potency as melatonin at MTi receptors and 17 times the potency at MT2 receptors. Adverse effects in trials so far suggest effects similar to placebo. 

Randomised trials A randomised, placebo-controlled trial of controlled-release melatonin (3 mg) for treating insomnia in children (N = 160, mean age = 6.6 years, 82% male) reported that the melatonin treatment was well tolerated with no adverse effects reported or observed and normal blood and urine analyses recorded across treatment groups [52 ]. 

Placebo-controlled studies Prolonged-release melatonin 2 mg at night (Circadin ) has been compared with placebo in a 6-month study of 791 adults with primary insomnia, of whom 534 took melatonin in the extension phase [45. The incidence and type of adverse events with melatonin and placebo were similar. Melatonin had no effect on vital signs, physical examination, electrocardiography, or laboratory tests, including prolactin, ACTH, T3, free T4, TSH, LH, FSH, estradiol in women, free and total testosterone in men, and cortisol before and after a Synacthen test. One patient taking melatonin had bouts of palpitation. There were no withdrawal effects after withdrawal of long-term melatonin. 

Circadin is a prolonged-release tablet containing melatonin 2 mg. It has received European Medicine Agency approval for treatment of primary insomnia. Adverse reactions are uncommon, but include headache, pharyngitis, back pain, and weakness. There do not appear to be withdrawal effects. 

Literature reviews A review of the literature on the use of melatonin to treat sleep disorders concluded that treatment is not associated with any significant or serious short-term or long-term adverse side effects and that the headache, confusion, dizziness, cough and rashes sometimes reported are cormnon symptoms in children and are most... 

A randomised, placebo-controlled trial examining 3 weeks of melatonin treatment (2.5 mg) for the treatment of sleep disturbances in 16 hypertensive patients (aged 45-64 years 56% female) treated with beta-blockers found that melatonin treatment was effective at improving sleep quality with no adverse side effects, tolerance or rebound insomnia observed [57=]. 

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