Monitor lithium levels in patients receiving telmisartan and hydrochlorothiazide and lithium. Therefore, monitor renal function and blood pressure periodically in patients receiving telmisartan and hydrochlorothiazide and NSAIDs. Hydrochlorothiazide Administration of a non-steroidal anti-inflammatory agent, including a selective COX-2 inhibitor, can reduce the diuretic, natriuretic, and antihypertensive effects of diuretics.
Source: FDA drug label - telmisartan and hydrochlorothiazide