Indicate the alfa1-selective antagonist:

Correct Answer: C

Rationale: Rationale: 1. Prazosin is an alpha1-selective antagonist used to treat hypertension by blocking alpha1 receptors in blood vessels. 2. Phentolamine (A) is a non-selective alpha-blocker. 3. Dihydroergotamine (B) is a 5-HT1 receptor agonist used for migraine. 4. Labetalol (D) is a non-selective alpha and beta blocker. Therefore, C (Prazosin) is the correct answer as it is a selective alpha1 blocker.

Correct Answer: C

Rationale: The correct answer is C: Diazepam. Diazepam is the most effective drug for stopping generalized tonic-clonic status epilepticus in adults due to its rapid onset of action and ability to terminate seizures quickly. It works by enhancing the inhibitory neurotransmitter GABA in the brain, suppressing seizure activity. Lamotrigine (A) is not recommended for acute seizure control. Ethosuximide (B) is used for absence seizures, not generalized tonic-clonic seizures. Zonisamide (D) has a slower onset of action and is not the first-line treatment for status epilepticus.

Correct Answer: C

Rationale: Rationale: Carbidopa is a peripheral dopa decarboxylase inhibitor. It does not cross the blood-brain barrier and prevents the conversion of levodopa to dopamine in the periphery, increasing levodopa availability in the brain. Tolcapone and Selegiline are central nervous system dopaminergic agents. Clozapine is an atypical antipsychotic used in schizophrenia.

Correct Answer: A

Rationale: Morphine is the correct choice because it is a potent opioid that acts as a vasodilator and reduces preload and afterload, making it beneficial in acute pulmonary edema by improving oxygenation and reducing anxiety. Codeine is a weaker opioid and not as effective in managing acute pulmonary edema. Fentanyl is a potent opioid but lacks the vasodilator effects of morphine. Loperamide is an opioid used for diarrhea and has no role in treating acute pulmonary edema.

Correct Answer: A

Rationale: Step 1: Antipsychotic drugs primarily act by blocking dopamine receptors, especially D2 receptors. Step 2: Blocking D2 receptors reduces dopamine activity, helping control psychotic symptoms. Step 3: Option A is correct as antipsychotics strongly block postsynaptic D2 receptors. Summary: - B is incorrect as stimulating D2 receptors would worsen psychotic symptoms. - C is incorrect as antipsychotics do not typically block NMDA receptors. - D is incorrect as antipsychotics primarily target dopamine receptors, not 5-HT2 receptors.