Hi Genevieve! - Most medications, when take on schedule will reach steady state within seven half-lifes; at that point (theoretically) the dose that you take equals the amount of drug and it's metabolites that are excreted.

The dosing regimen for propranolol depends largely on the dosage form of the drug (esp. long-acting v. regular), with the gamut running from once per day to four times per day, depending upon the total daily dose, how fast one excretes the drug, and which formulation of the drug you are taking.

I hope that this does help some. - Cam