Can melatonin provide benefits to those with Parkinson’s?

I am an 84-year-old woman. Unfortunately, I have been diagnosed with Parkinson’s disease this past month. (Of course, I am mightily researching now.)

A friend of ours, who has had Parkinson’s for six years, is very much impressed with melatonin. Have you heard the same?

Even if it turns out that it is not all helpful for Parkinson’s, there seems to be multiple other benefits, making it worthwhile to give it a try.

I’m sending you two papers about it, and I would so appreciate your comments.

— A.R.

There are theories why melatonin might be protective in the brains of people with Parkinson’s disease, and there’s some preliminary research in animals to suggest there may be some benefit. Unfortunately, there isn’t any good evidence I could find in humans that shows any benefit to melatonin beyond modest sleep improvement in some people with sleep disturbances and Parkinson’s disease.

I read the papers you sent, and it is clear that they are written by people who are passionate, but there just aren’t good enough data to support the use of melatonin to treat motor or nonmotor symptoms of Parkinson’s, nor to slow down the progression.

It is extremely common that early papers, often with small numbers of subjects, show a big benefit for a new treatment, but larger and more stringently controlled studies fail to confirm that benefit. Advances in clinical medicine tend to happen slowly, since proving a new treatment effective is generally difficult, expensive and time-consuming. Wise clinicians seldom rush to new treatments, although there certainly have been notable exceptions. I doubt melatonin will prove to be a big benefit in Parkinson’s; though, I do keep an open mind and would love to be proven wrong.

I’m a 66-year-old man who has been losing hair since my 20s. I’m in pretty good health and still young at heart, so I decided to try topical minoxidil. While I have lost my ordinary head of hair, I still have thin wisps of hair across the top of my head. (I’m not “shiny head bald.”) When I read the instructions of the minoxidil, it warned against using this for bald men, but it didn’t specify why.

Do you know if I could be doing harm or risking my health by using minoxidil, even if it likely won’t produce the desired results? I figure it doesn’t hurt to try, but the warning against it has me concerned.

— D.E.

Topical minoxidil (solution or foam applied to the scalp, not minoxidil taken by mouth) is pretty safe. It can be irritating to the scalp, but seldom has other ill effects. Men who have had hair loss for many years, who don’t have nonvellous hair (i.e., “peach fuzz”), and who have larger amounts of baldness are less likely to get a response, but are not at increased risk from a trial of minoxidil.

You should know that men often get increased hair shedding when first starting minoxidil, which stops after about two months. It takes at least four to eight months for hair regrowth to start, and it’s recommended to use the medication for a year before making an assessment of whether it’s effective (photos may help you decide). Finally, if you stop the medicine, all the benefit you had from treatment will be lost within a month or two.