A 45-year-old man with HIV on ART develops severe hypersensitivity reaction with fever, rash, and gastrointestinal symptoms after starting a new NRTI. Genetic testing reveals HLAB*5701 positivity. Which drug is contraindicated for life in this patient?
- A Zidovudine
- B Abacavir ✓
- C Stavudine
- D Didanosine
Correct answer: B. Abacavir
Explanation
Abacavir causes a potentially fatal hypersensitivity syndrome in HLAB*5701-positive patients. Genetic screening before abacavir initiation is mandatory, and the drug is permanently contraindicated in positive individuals. Zidovudine causes myelosuppression, stavudine causes peripheral neuropathy and lactic acidosis, and didanosine causes pancreatitis, but none have this specific pharmacogenetic association.
Reference: Katzung Basic and Clinical Pharmacology, 15th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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