– (±)-Penbutolol ((Rac)-Penbutolol) is the racemic form of Penbutolol. It acts as an orally active β-adrenergic receptor antagonist. (±)-Penbutolol mitigates the tachycardia induced by exercise, reduces the increase in peak expiratory flow rate (PEFR) caused by physical activity, and decreases plasma renin activity (PRA) at rest. The peak plasma concentration of this compound is achieved one hour after oral administration, with a half-life of 4.5 hours, and it is metabolized into active metabolites in the body. This compound is utilized in research related to cardiovascular diseases.