Regarding secondary prophylaxis of rheumatic fever, a 14-year-old boy weighing 45 kg is to receive monthly benzathine penicillin G. The correct single intramuscular dose is:
- A 300000 units every 3 weeks
- B 600000 units every 4 weeks
- C 1200000 units every 4 weeks ✓
- D 1200000 units every 3 weeks
Correct answer: C. 1200000 units every 4 weeks
Explanation
For secondary prophylaxis, benzathine penicillin G is given as 1200000 units intramuscularly every 4 weeks in children above 27 kg, and 600000 units in those at or below 27 kg. This 45 kg adolescent therefore receives 1.2 million units monthly. The 600000 unit dose applies to smaller children, and every-3-week dosing is reserved for selected very high-risk cases rather than routine practice.
Reference: Park's Textbook of Preventive and Social Medicine, 26th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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