I've had ED issues from prescription Adderall in the past which has improved since getting off of it. Now everything that has alleged ED side effects scare me to death. Ironically I have never had ED issues in the past from AAS even on heavier cycles. Long story short, I ran some Deca earlier in the year @ 300 mg /wk (basically to try to alleviate some nagging joints) and got quite the opposite, a raging boost in sex drive and absolutely ZERO ED issues. I know we all differ but from what my research found it's usually larger dosages 600mg+ that cause issues and even some of that can be negated by running a small dosage of Caber or Prami. I'm assuming your buddy is running some testosterone along side with his Deca? Is he taking anything else?