A 59-year-old man complains of nocturia, urinary frequency, and an inability to urinate forcefully and empty his bladder. Following a complete workup, he was diagnosed with benign prostatic hypertrophy (BPH). We start daily therapy with tamsulosin. Which of the following is the most likely side effect the patient may experience from the tamsulosin, and about which he should be forewarned?

Correct Answer: C

Rationale: The correct answer is C: First dose hypotension. Tamsulosin is an alpha-1 blocker commonly used for BPH. It can cause orthostatic hypotension, especially after the first dose due to sudden vasodilation. This side effect is important to be forewarned about to prevent falls or accidents. Bradycardia (choice A) is not a common side effect of tamsulosin. Increased risk of statin-induced skeletal muscle pathology (choice B) is unrelated to tamsulosin. Photophobia and painful responses to bright lights (choice D) are not associated with tamsulosin use.

Correct Answer: B

Rationale: The correct answer is B: Isoprenaline. Isoprenaline directly stimulates both β1 and β2 adrenoceptors. It is a non-selective β-adrenergic agonist, leading to increased heart rate (β1 stimulation) and bronchodilation (β2 stimulation). Incorrect choices: A: Noradrenaline mainly acts on α-adrenoceptors. C: Salbutamol is a selective β2 agonist, not stimulating β1 receptors. D: Amphetamine primarily acts on catecholamine release and reuptake inhibition, not direct β-adrenoceptor stimulation.

Correct Answer: B

Rationale: The correct answer is B: Hyoscine. Muscarinic receptors can be stimulated by Pilocarpine, Acetylcholine, and Neostigmine, as they are known agonists of muscarinic receptors. Hyoscine, also known as scopolamine, is an antagonist of muscarinic receptors, blocking their stimulation. This makes it the exception among the listed drugs.

Correct Answer: C

Rationale: The correct answer is C: Hypotension. Chronic tobacco smoking typically causes vasoconstriction, leading to increased blood pressure rather than hypotension. Peripheral vascular disease (A), cardiac arrhythmias (B), and increased gastric secretion (D) are common effects of chronic tobacco smoking due to the harmful impact on blood vessels, heart function, and gastrointestinal system.

Correct Answer: D

Rationale: Propranolol is a non-selective beta-blocker which primarily affects the heart. Bronchodilation is not a common effect of propranolol due to its non-selectivity for beta-2 receptors in the lungs. Therefore, choice D is the correct answer. Choices A, B, and C are correct because propranolol typically causes negative inotropic effect (reduced force of heart contraction), negative chronotropic effect (slowing of heart rate), and slowing of A-V conduction (delay in electrical signal between atria and ventricles), respectively.