Which of the following antipsychotics (in excess dose) is responsible for cardiac arrhythmias?

Correct Answer: C

Rationale: Thioridazine has been associated with QT prolongation and a higher risk of cardiac arrhythmias.

Correct Answer: A

Rationale: The correct answer is A because alcohol can enhance the side effects of anticholinergic therapy, such as dizziness and drowsiness. Alcohol can also worsen symptoms of Parkinson's disease. Choices B and C are incorrect because there is no direct interaction between cigarettes, caffeine, and anticholinergic therapy. Choice D is incorrect because while it may help relieve dry mouth, it is not specifically related to the use of anticholinergic therapy for Parkinson's disease.

Correct Answer: A

Rationale: Carbimazole (choice A) and Propylthiouracil (choice D) treat hyperthyroidism by inhibiting thyroid hormone synthesis, Propranolol (choice C) manages symptoms. Carbamazepine (choice B), an anticonvulsant, is unrelated, making it the exception. This clarifies antithyroid therapy.

Correct Answer: C

Rationale: Ethosuximide (choice C) treats absence seizures by reducing T-type calcium currents, ideal for brief consciousness lapses. Alprazolam (choice A), Diazepam (choice B), and Midazolam (choice D), benzodiazepines, aren't first-line for absence. Ethosuximide's specificity is key.

Correct Answer: B

Rationale: Darifenacin, a muscarinic receptor antagonist used for urinary tract infections, may enhance the action of vecuronium by reducing the risk of cholinergic side effects, such as bradycardia or bronchoconstriction, associated with muscle relaxants. Gentamicin, Timolol, Latanoprost, and Lovastatin are unlikely to have a significant impact on the action of vecuronium in this context.