The adverse effects of sympathomimetics include all of the following EXCEPT:

Correct Answer: A

Rationale: The correct answer is A: Drug-induced parkinsonism. Sympathomimetics stimulate the sympathetic nervous system, which can lead to adverse effects like cerebral hemorrhage, pulmonary edema, myocardial infarction, and ventricular arrhythmias due to increased heart rate and blood pressure. However, they do not cause drug-induced parkinsonism, which is associated with medications that affect dopamine levels in the brain. Therefore, choice A is the correct answer. Choices B, C, and D are incorrect because sympathomimetics can indeed lead to these adverse effects due to their actions on the sympathetic nervous system.

Correct Answer: A

Rationale: Sure! Valproate is the correct answer as it is used as an anti-absence drug due to its effectiveness in treating absence seizures. Valproate works by enhancing the activity of a neurotransmitter called gamma-aminobutyric acid (GABA), which helps to calm overactive brain activity that causes absence seizures. Phenobarbital, Carbamazepine, and Phenytoin are not typically used to treat absence seizures, as they are more commonly used to treat other types of seizures such as tonic-clonic seizures or focal seizures.

Correct Answer: B

Rationale: Levodopa is the precursor of dopamine as it is converted into dopamine in the brain. Bromocriptine is a dopamine agonist, not a precursor. Selegiline is a MAO-B inhibitor that helps preserve dopamine, not a precursor. Amantadine is an antiviral drug with unclear mechanisms regarding dopamine production. Therefore, B is the correct answer.

Correct Answer: C

Rationale: The correct answer is C: Meperidine. Meperidine is commonly used in obstetric labor due to its rapid onset of action and short duration, making it suitable for managing acute pain during labor without affecting the fetus adversely. Fentanyl (A) is also a potent opioid analgesic, but its rapid onset and short duration make it more suitable for surgical procedures. Pentazocine (B) is a partial opioid agonist-antagonist and is not commonly used in obstetric labor due to its limited efficacy in managing severe pain. Buprenorphine (D) is a partial agonist with a long duration of action and is typically used for opioid maintenance therapy rather than acute pain management during labor.

Correct Answer: B

Rationale: The correct answer is B: Tramadol. Tramadol is a mixed (opioid/non-opioid) agent as it acts on opioid receptors and inhibits the reuptake of serotonin and norepinephrine. This dual mechanism provides both opioid and non-opioid effects. Paracetamol (A) is a non-opioid analgesic, sodium valproate (C) is an anticonvulsant, and butorphanol (D) is a mixed opioid agonist-antagonist but not typically used as a tick mixed agent.