Suggest Treatment For Hair Fall While On Flomax, Niaspan, Lovaza And Synthroid

I am 58 years old. I take vitamins, fomax, Niaspan and Lovaza, and Synthroid. My hair is continuously shedding. It has gotten to the point that the crown of my hair is VERY thin. I have read that large quantities of fish oil and also Niaspan cause this is some people. I have also read Synthroid causes some to lose their hair even though this is supposed to prevent hair loss. Any suggestions? I am 5'3" and weigh 125.