A patient with chronic kidney disease requires a tetracycline for treatment of rickettsial infection. Which tetracycline is the preferred and safest choice in significant renal impairment?
- A Tetracycline
- B Doxycycline ✓
- C Demeclocycline
- D Minocycline
Correct answer: B. Doxycycline
Explanation
Doxycycline is predominantly eliminated in the faeces, both unchanged and as inactive conjugates, so its half-life is minimally prolonged in renal failure and it does not accumulate to toxic levels. Older tetracyclines such as tetracycline and demeclocycline are renally excreted and worsen uraemia through their antianabolic effect on protein synthesis. Minocycline is largely hepatically metabolised but accumulates less predictably than doxycycline in this setting.
Reference: Katzung Basic and Clinical Pharmacology, 16th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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