You're talking about
M1T correct? How old is he? If he's under 21, he shouldn't use it. He shouldn't start at a dose higher than 10mg per day and never go above 20-30mg per day if he can tolerate it.
Define short-term and long-term? If by short-term you mean a two week cycle at 10-20mg per day, probably not much harm. Long-term for
M1T is 4 weeks+ at 10-20mg per day or more. At a month and over his natural testosterone production will lower significantly. Also, there will be appreciable liver toxicity. Also, he'll probably have increased acne and
possibly a pronounced aggressive disposition (not roid rage, just heightened aggressiveness).
If you want to test whether he knows what he's doing, first, does he pass those tests mentioned above? Then ask him this question: "What's your plan for PCT (post cycle therapy)?" If he can't give you a detailed protocol (e.g. his answer should be something like this -- "Immediately post cycle I'll use 20-40mg nolvadex everyday for 3-4 weeks" or "I'm using Clomid" or something to that effect.
Also, he should have his blood work done before and after cycle. And have a liver panel done.
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