Two years ago I had successful surgery and radiotherapy to treat a brain tumour. During radiotherapy, most of my hair came out and grew back a few months later. However, it is still patchy in the area of the treatment - the crown. Will it grow back?

First, congratulations on the recovery from the tumour. Sadly, after two years, it is unlikely that your remaining thin patch will improve much more - the best improvement takes place within the first year or so after surgery. Your doctor may well advise applying 2% minoxidil solution to the area twice daily for two weeks, to see if it might improve, but please don't do this without getting his or her go-ahead. If after two weeks you have seen no improvement, there is little point in continuing the treatment.

I'm 28, physically fit and healthy. For as long as I can remember, I have had terrible nightmares every night. I can't recall a nice or even a neutral dream. I wake up, four or five times, in a state of fright. Is it a sign of an illness, or something I just have to learn to put up with? Normal sleeping tablets rarely work in cases such as yours, nor does the usual advice about rest or exercise before sleeping. You may have pathological sleep patterns that can almost certainly be corrected with a visit to a sleep laboratory - your GP will refer you to a regional sleep centre, where your levels of sleep can be examined in detail. You may then be given a specific drug to solve the problems.

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