Other antihypertensive drugs - additive effect or potentiation. Cholestyramine and colestipol resins - Absorption of hydrochlorothiazide is impaired in the presence of anionic exchange resins. Single doses of either cholestyramine or colestipol resins bind the hydrochlorothiazide and reduce its absorption from the gastrointestinal tract by up to 85 and 43 percent, respectively. Corticosteroids, ACTH - intensified electrolyte depletion, particularly hypokalemia. Lithium - should not generally be given with diuretics.
Diuretic agents reduce the renal clearance of lithium and add a high risk of lithium toxicity.