This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Anti Microbial, Subject name: Pharmacology
Drug of choice for syphilis during pregnancy is 
Select and explain. 
A. Ampicillin, B. Erythromycin, C. Benzathine penicillin, D. Tetracyclines
C: Benzathine penicillin
Answer: C: Benzathine penicillin 
Explanation: Ans. c (Benzathine penicillin). (Ref. KD Tripathi - 4th/ 741, 751; William's Obstetrics - 780)# Penicillin is DOC during pregnancy as it also protects the newborn from developing syphilis.# If patient is allergic to penicillin, desensitize the patient & give penicillin (not erythromycin).DOC for syphilisPenicillinAlternative to penicillinErythromycinDuring pregnancyDOC (even if patient is allergic to penicillin) is Penicillin. (Because erythromycin never protect baby from developing syphilis)