At this point I had not made a connection between Phentermine
and hives. Then I went back on
Phentermine again at the beginning of August,
and hives came on vehemently, all over the body. Mine are small red dots primarily, though at the beginning, they were large. Typically now they vary in size, texture, etc. I went online to find out that, in fact, urticaria can be a serious side-effect of Phentermine. I went to my weight loss doctor, and he told me that my urticaria was stress-related.