Actually I've been googling around since you've said this, and I can find WHO and CDC booklets indicating that PrEP is generally safe. In fact, the WHO indicate

Actually I've been googling around since you've said this, and I can find WHO and CDC booklets indicating that PrEP is generally safe. In fact, the WHO indicates that PrEP is as safe as placebo in the populations that have been studied. http://apps.who.int/iris/bitstream/handle/10665/197906/WHO_HIV_2015.48_eng.pdf http://apps.who.int/iris/bitstream/handle/10665/197906/WHO_H... It's interesting because some of the gay men I spoke with about PrEP seemed to think there were significant risks of kidney damage from long-term use. I wonder where they got their information from.