Drug of choice for prophylaxis in diphtheria is:
The options for chemoprophylaxis of diphtheria include Erythromycin (7-10 days oral course) or Benzathine Penicillin G (single intramucular dose). Ref: Erythromycin: A motilin Agonist and Gastrointestinal Prokinetic Agent: American Journal of Gastroenterology 88 (4): 485-90; Basic and Clinical Pharmacology By Katzung, 9th Edition, Section VIII; Park's Textbook of Preventive and Social Medicine By K. Park, 18th Edition, Page 104 and 19th Edition, Page 893
Erythromycin
Doxycycline
Tetracycline
Clindamycin