Melatonin – Good for Glaucoma as well as Sleep?
What is Melatonin?
Melatonin (scientific name: N-acetyl-5-methoxytryptamine) is a hormone naturally produced in the brain and retina. It can also be found in a number of plant-based foods such as cherries, walnuts, tomatoes, and strawberries. It has a number of functions, the best known of which is to regulate sleep.
Evidence that Melatonin can be effective in the treatment of Glaucoma
As little as 500mcg (0.5mg) of Melatonin has been shown to lower intraocular pressure (IOP) in healthy men. A larger dose (10mg) was demonstrated to lower IOP when taken prior to cataract surgery. This effect appears to be due to Melatonin’s actions on both the alpha and beta adrenergic receptors as well as carbonic anhydrase. In essence, Melatonin acts on three of the four IOP lowering pathways currently targeted with modern prescription ocular therapy (beta-blockers, alpha-agonists, and carbonic anhydrase inhibitors).
Melatonin has other potential benefits to those with glaucoma. For example, it is a powerful antioxidant. Melatonin has also been shown to provide a neuroprotective effect. This neuroprotective effect appears to be enhanced when both Resveratrol and Melatonin are present.
Potential Side Effects and Risks:
Melatonin has been taken in single doses as high as 500mg without notable side effects. Long term, taking up to 5mg per day of Melatonin appears to be safe.
Potential Drug Interactions
Melatonin may lower blood pressure. In those whose blood pressure is not well-controlled this could be a good thing. However, care should be taken when used along with other blood-pressure lowering medications such as captopril (Capoten), enalapril (Vasotec), losartan (Cozaar), valsartan (Diovan), diltiazem (Cardizem), amlodipine (Norvasc), hydrochlorothiazide (HydroDIURIL), furosemide (Lasix), as well as many others.
I recommend that my patients begin taking a minimum of 500mcg (0.5mg) of Melatonin thirty minutes prior to going to bed at night. If they are also having difficulty falling asleep then I will instruct them to slowly increase the dose until they have reached a maximum dose of 5mg per night. As both glaucoma and sleep disturbance are more common as we age, supplementing with Melatonin provides a dual benefit.
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Don’t delay getting checked for glaucoma.
Make an appointment with an eye doctor in your area now. If you live in the greater Los Angeles area and would like Dr. Richardson to evaluate your eyes for glaucoma call 626-289-7856 now. No referral required. Appointments are available, Tuesday through Saturday.