Which tetracycline derivative produces nephrogenic diabetes insipidus and has been therapeutically exploited for this effect in the management of the syndrome of inappropriate antidiuretic hormone secretion?

• A Minocycline
• B Tigecycline
• C Lymecycline
• D Demeclocycline ✓

Explanation

Demeclocycline uniquely induces a state resembling nephrogenic diabetes insipidus by blunting the antidiuretic hormone-mediated water reabsorption in the collecting ducts. This adverse effect has been turned into a therapeutic use in chronic SIADH, where it promotes free water excretion and corrects hyponatremia. Its onset takes several days and it carries a risk of nephrotoxicity, so it is now less favored than vaptans, but the association remains a standard examination fact. Minocycline causes vestibular toxicity rather than this effect.

Reference: Goodman and Gilman's The Pharmacological Basis of Therapeutics, 14th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

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