So sorry chikky42, I still haven't been able to find a match for your pill.
I have been through all the generic
Atenolol 50 mg pills available in Canada...
Apo-Atenol® 50 mg white, round, scored tablet, identified "APO" over "A50" on one side.
Gen-Atenolol® 50 mg white, round tablet, with "[u]G</u>" over "G" on one side and "[u]AT</u>" over "50" on the other.
Novo-Atenol 50 mg white, round, scored tablet engraved with arched novo over 50 on scored side.
Nu-Atenol 50 mg white, round tablet, scored and identified "NU" over "50" on one side.
PMS-Atenolol 50 mg white-to-off-white, scored, film-coated tablet, marked with "pms-ATENOLOL 50" on one side.
Rhoxal-atenolol 50 mg white, round tablet, embossed A50 and scored on one side, and plain on the other.
Riva-Atenolol® 50 mg white tablet, embossed with "Riva/50" on one side.
Tenolin® 50 mg white-to-off-white, scored, film-coated tablet, embossed with "Tenolin 50" on one face.
Tenormin® 50 mg scored, white-to-off-white, film-coated tablet, embossed with "TENORMIN 50" on one side.
Is it possible to ask the pharmacist who dispensed the medicine?