Do any of you make your own protein shakes? I got my Dad some weight gainer protein powder and it says on the side of the container "do not use if you have a medical condition." Is that written on all of them? You think this is safe for him?

Brandi, daughter of:
Jack, age 69, non-smoker, BOT primary, Stage 4, HPV+
1/28/2013: Surgery. All cancerous masses removed. Dad is CANCER FREE!!!
2/26/2012: Beginning of TX. Weekly chemo: Carboplatin and Taxol. Daily RT (about 40 total)
4/25/2013: Will be last day of TX, both chemo and RT