I’m not sure what the rationale is for starting with extended release. I would think that testing your response with immediate release dosing would make more sense, but of course I am not a doctor. I take 10 mg twice a day and, for me, it doesn’t affect my BP much, but everyone is different. You can take the immediate release tablets every few hours so that you don’t get a treatment gap. Then he could experience with different doses. Then, if propranolol suits you, he could switch you to extended release.