Dear Kevin,
It is unlikely that the hair thinning is caused by the Zocor. However, anaectodally i have seen patients on Lipitor another cholesterol lowering medication have hair loss.
I would suggest trying to stay on the ZOCOR ana maintain an LDL <130 and an HDL >45.
I am a 44 year old female, had a 5way bypass 4 years ago and have been very distressed with the hair loss I have. My doctor took me off of prevachol and put me on lipitor to try to reduce the loss to no avail it seems to be worse! I was on zocor right after surgery and hair loss was not as bad.