Repeated USMLE Questions Step 1- 174

A 34-year-old man newly immigrant from Kenya presents to your office for fever, sore throat and general aches. He has a long history of malaria and takes daily primaquine. Throat swab reveals streptococcal infection. You decide to prescribe an antibiotic.

Which of these antibiotics is contraindicated for this patient?

A- Ampicillin

B- Amoxicillin

C- Ciprofloxacin

D- Erythromycin

Answer:






Erythromycin blocks the metabolism of primaquine by the liver through depressing the P450 system. This leads to accumulation of primaquine causing toxicity.

The correct answer is D