My mother has been taking Effexor for about four months, now and ...

My mother has been taking Effexor for about four months, now and is having a side-effect the doctor claims is not related to the drug. SHE IS LOSING HER HAIR IN HUGE CLUMPS. SHE HAS LARGE BALD SPOTS!!! The doctor ran some blood tests, reported to her the fact they were all okay and says that it is probably just stress. He also says he thinks it will grow back but if not she can always consider hair transplants....gee, thanks!!!! I mean, stress? Come on, the woman is 55 years old and has had plenty of stress before this.........I just want to help her so any info would be greatly appreciated!!!!!