I lost about 70% of my hair from around March to June of this year, it was very noticeable and I now have hair extensions to add volume back. It's not an ideal solution, due to the expense but for now it solves the problem atleast.
I went to see a Trichologist, basically someone who specialises in hair, and she said the problem was described as chronic telogen effluvium and for me it was a combination of low iron levels, low b12 levels, general poor nutrition and taking azathioprine (which I have now stopped). I was also asked to get blood tests to confirm nothing else was going on. I now take various supplements to correct the above problems along with some vitamins especially targeted at skin, hair and nails. I am also applying something called Minoxidil 4% in the form of a topical solution to my scalp, twice a day which has been proven to stimulate the hair follicles. I believe this is available over the counter under the trade name Rogaine in a lesser strength.
Luckily I do have a quite a lot of new growth coming through now, although obviously my hair will time time to totally thicken out again. I'm just grateful this isn't going to be a long term problem, I would think in these circumstances in rarely is though. I'd suggest maybe your wife brings it up with her care provider and see if they have any suggestions as to why this is happening in her particular case and to see if there are any targeted solutions.
