Which of the following sympathomimetics is an effective mydriatic?

Correct Answer: B

Rationale: The correct answer is B: Phenylephrine. Phenylephrine is an effective mydriatic because it acts on alpha-1 adrenergic receptors in the eye, causing pupillary dilation. Salmeterol (A) is a long-acting beta-2 agonist used for asthma, not mydriasis. Dobutamine (C) is a beta-1 agonist used for cardiac support. Norepinephrine (D) is a non-selective adrenergic agonist used for hypotension, not for mydriasis.

Correct Answer: D

Rationale: The correct answer is D: All of the above. Carbamazepine, valproate, and phenytoin are all antiepileptic drugs used to treat partial and generalized tonic-clonic seizures. Each drug works through different mechanisms to help control seizure activity. Choosing "All of the above" ensures that all appropriate treatment options are considered for managing these types of seizures. Options A, B, and C alone are incorrect because each drug individually is effective but may not cover all seizure types.

Correct Answer: C

Rationale: Certainly! Benztropine is preferred in drug-induced parkinsonism as it acts as an anticholinergic agent, counteracting excess acetylcholine caused by certain drugs. Levodopa (A) and dopamine (D) are not effective as they can worsen symptoms. Bromocriptine (B) is a dopamine agonist used in idiopathic Parkinson's disease, not drug-induced parkinsonism.

Correct Answer: D

Rationale: The correct answer is D: Therapeutic doses of opioid analgesics do not affect body temperature. Opioid analgesics primarily act on the central nervous system to provide pain relief, without directly impacting body temperature regulation. Choices A and B are incorrect as opioid analgesics do not have a significant impact on altering body temperature. Choice C is incorrect as opioid analgesics do not affect body heat loss mechanisms. Thus, the correct answer is D because opioid analgesics do not have a direct effect on body temperature regulation.

Correct Answer: D

Rationale: The correct answer is D: Amitriptyline. Amitriptyline is a tricyclic antidepressant that is commonly used for both depression and chronic pain conditions due to its analgesic properties. It works by increasing the levels of certain neurotransmitters in the brain, such as serotonin and norepinephrine, which can help alleviate both mood symptoms and pain. Choice A (Fluoxetine) is an SSRI antidepressant that does not have significant analgesic properties. Choice B (Moclobemide) is a reversible MAOI antidepressant that also lacks analgesic effects. Choice C (Tranylcypramine) is an irreversible MAOI antidepressant and does not have analgesic activity. In summary, amitriptyline is the correct answer because it is an antidepressant with proven analgesic effects, while the other choices do not possess these dual properties.