Acute effects of varying doses of propranolol upon oxygen haemoglobin affinity in man.

1 The effect of propranolol 2 h following doses of 10, 30, or 100 mg upon the blood oxygen-haemoglobin dissociation curves has been studied in four normal subjects. 2 The pO(2) at 50% saturation (p50) was not changed significantly under control conditions or after 10 and 100 mg doses. There was a just significant increase of 2 mmHg in the p50 value after the 30 mg dose. 3 There was no significant change in red cell adenosine triphosphate or 2,3-diphosphoglycerate nor in plasma phosphate. 4 There was no correlation between plasma propranolol concentration and changes in blood p50.