In my view, there are 3 plausible scenarios:

1. He is lying about it and not taking it because he wants to prove he was right that it is OK to take or whatever. my view: plausible.

2. He is actually taking it. my view: implausible, with his weight, heart condition and hypertension no doctor would prescribe it.

3. The doctor gave him a placebo to get him off his back about it. my view: highly plausible.