Google expressly does not do that kind of retargeting. Its policies prohibit retargeting based on "health or medical information": https://support.google.com/ad

Google expressly does not do that kind of retargeting. Its policies prohibit retargeting based on "health or medical information": https://support.google.com/adwordspolicy/answer/143465?hl=en https://support.google.com/adwordspolicy/answer/143465?hl=en I know that the previous post didn't mention Google, but people might leap to the wrong conclusion. I don't know what Yahoo and Microsoft's policies are.