<prompt> A patient on lithium therapy was found to be hypeensive also. Which of the following antihypeensive drugs is contraindicated in a patient on lithium therapy in order to prevent toxicity?ClonidineBeta blockersCalcium channel blockersDiuretics  <response>: Diuretics thiazide, furosemide by causing Na loss promote proximal tubular reabsorption of Na as well as Li --plasma levels of lithium rise. ref : KD Tripati 8th ed. 