Side effect of dihydrotachysterol is:

Correct Answer: A

Rationale: The correct answer is A: Hepatic toxicity. Dihydrotachysterol is a vitamin D analog used to treat hypoparathyroidism and hypocalcemia. It can cause liver damage as a side effect due to its metabolism in the liver. General malaise (B), lymphocytopenia (C), and hypertension (D) are not typically associated with dihydrotachysterol use. Therefore, the correct answer is A based on the drug's mechanism of action and known side effects.

Correct Answer: B

Rationale: The correct answer is B: Lincomycin. Lincomycin belongs to the lincosamides class of antibiotics, which also includes clindamycin. Lincomycin works by inhibiting bacterial protein synthesis. Erythromycin (A) is a macrolide antibiotic, not a lincosamide. Azithromycin (C) is another macrolide antibiotic. Aztreonam (D) is a monobactam antibiotic, not a lincosamide. Therefore, the correct answer is B because it is the only drug belonging to the lincosamides class.

Correct Answer: B

Rationale: Step 1: Isoniazid is a hydrazide of isonicotinic acid, making it the correct antimycobacterial drug. Step 2: Rifampin is a rifamycin antibiotic, not a hydrazide of isonicotinic acid. Step 3: Ethambutol is an antimycobacterial drug but not a hydrazide of isonicotinic acid. Step 4: Pyrazinamide is an antimycobacterial drug but not a hydrazide of isonicotinic acid.

Correct Answer: A

Rationale: The correct answer is A: Praziquantel. Praziquantel is the drug of choice for treating neurocysticercosis as it is effective against the tapeworm causing this condition. It works by affecting the tapeworm's cell membrane, leading to paralysis and death of the parasite. Pyrantel is used for treating intestinal parasites, not neurocysticercosis. Piperazine is used for treating roundworm infections. Bithionol is used for treating certain types of flukes. Therefore, the most appropriate choice for neurocysticercosis treatment is praziquantel due to its effectiveness against the tapeworm causing the condition.

Correct Answer: B

Rationale: The correct answer is B: Anastrozole. Aromatase inhibitors block the enzyme aromatase, which converts androgens into estrogens. Anastrozole specifically inhibits aromatase, reducing estrogen levels. Octreotide (A) is a somatostatin analogue, Flutamide (C) is an androgen receptor antagonist, and Tamoxifen (D) is a selective estrogen receptor modulator (SERM), not an aromatase inhibitor. Thus, the only drug among the choices that directly targets aromatase is Anastrozole.