I was 2 months shy of my 70th birthday when i received my stem cell infusion. The conditioning regimen with heavy duty chemo drugs occurred over 5 days. The 6th day was my infusion day. The side effects of the last chemo drug (Melphalan) were quite arduous for me (Melphalan was administered the day before my infusion). Side effects from the Melphalan persisted, even after I was released from the hospital & it does take weeks to get your energy back. Everyone is different. I received an autologous transplant, which supposedly has less side effects than a donor transplant (allogeneic).