@barbaraww
What is the pattern of hair loss?
There are a number of different ways that people lose hair
Male pattern baldness (we have all seen this)
Women often lose hair over the top of their head (often looks like the parting is widening) and it thins, and goes drier and lightens a bit in colour - this is often hormonal, especially with PCOS or menopause
Alopecia often has patches, anywhere on the head, of total baldness. Lots of different causes, including stress.
Have a look at the pics on this page, showing the different patterns. Does anything ring a bell?
http://www.worldhairresearch.com/?tag=hair-loss-scale
I had a period of several years, in my 30s, when the hair on the top of my head when lighter, drier, coarser and thinner. Nothing I did to it helped. They later diagnosed me with a hormonal imbalance, treated it, and my hair fully recovered.
I'm afraid I've no experience of medication causing hair loss, so can't comment on that.