Which of the following is a common adverse reaction associated with Propranolol Hydrochloride?

Propranolol Hydrochloride, a non-selective beta-blocker, is commonly associated with bradycardia as an adverse reaction. This decrease in heart rate occurs because beta-blockers inhibit the effects of adrenaline on beta-adrenergic receptors, which leads to a reduction in heart rate and myocardial contractility.

While hypotension, which can result from the drug's ability to lower heart rate and reduce cardiac output, is also a potential adverse effect, bradycardia is often listed as a more direct and frequent consequence of using propranolol.

Hypertension is not typically associated with this medication; rather, propranolol is used to treat conditions characterized by high blood pressure, and headache, while it can occur in some patients, is less specific than bradycardia as a common adverse reaction for propranolol. Thus, bradycardia stands out as a hallmark adverse effect linked to its pharmacological action.