I don't know whether I'm looking at a rule or a guideline.
The CAA website says " A full report (from cardiologist or GP) should confirm that the BP has stabilised on acceptable treatment (for a minimum of 2 weeks) and that the pilot has no treatment-related side-effects. Attention to risk factors should be apparent. If satisfactory a fit assessment can be made."
I don't fancy betting my licence against what would amount to 7 days of not flying, if my usual days off are taken into account.