NSAIDs Thiazide diuretics

Abciximab, aminophylline, amiodarone, amrinone, aspirin, carbamazepine, chlorpromazine, danazol, diltiazem, eptifi-batide, heparin, histamine2-receptor antagonists, low molecular weight heparins, methyldopa, milrinone, procainamide, quinidine, quinine, NSAIDs, thiazide diuretics, ticlopidine, tirofiban, and valproic acid... 

A whole host of drugs can give rise to purpura, the most common being NSAIDs, thiazide diuretics, phenothiazines, cytostatics, gold, penicillamine, hydantoins, thiouracils, and sulfonamides. 

Drugs that may be affected by NSAIDs include the following Aminoglycosides, anticoagulants, ACE inhibitors, beta blockers, cyclosporine, dextromethorphan, digoxin, dipyridamole, hydantoins, lithium, loop diuretics, methotrexate, penicillamine, potassium-sparing diuretics, sympathomimetics, theophylline, thiazide diuretics. 

Lithium intoxication can be precipitated by the use of diuretics, particularly thiazides and metola-zone, and ACE inhibitors. NSAIDs can also precipitate lithium toxicity, mainly due to NSAID inhibition of prostaglandin-dependent renal excretion mechanisms. NSAIDs also impair renal function and cause sodium and water retention, effects which can predispose to interactions. Many case reports describe the antagonistic effects of NSAIDs on diuretics and antihypertensive drugs. The combination of triamterene and indomethacin appears particularly hazardous as it may result in acute renal failure. NSAIDs may also interfere with the beneficial effects of diuretics and ACE inhibitors in heart failure. It is not unusual to see patients whose heart failure has deteriorated in spite of increased doses of frusemide who are also concurrently taking an NSAID. 

Drugs that can precipitate lactic acidosis in patients taking metformin include ACE inhibitors, thiazide diuretics, NSAIDs, and drugs such as furosemide, nifedipine, cimetidine, amiloride, triamterene, trimethoprim, and digoxin, which are all secreted in the renal tubules, compete with metformin, and can contribute to increased plasma metformin concentrations (76). 

Sulfonylureas In acute poisoning with sulfonylureas, the stomach should be washed and treated with activated charcoal, and hypoglycemia must be treated. Sulfonylureas interact with oral contraceptives, thiazide diuretics, corticosteroids, adrenaline, chlorpromazine, ACE inhibitors, some NSAIDs, antihistamines, anticoagulants, MAOIs, antidepressants, and many other drugs. Care must be exercised when treating with sulfonylureas. 

Non-steroidal anti-inflammatory drugs (NSAIDs) are often reported to interfere with the blood pressurelowering action of thiazide diuretics (SED-14, 667). In 17 women with arthritis and hypertension taking fosinopril and hydrochlorothiazide, ibuprofen, sulindac, and nabu-metone, each for 1 month, had no effect on mean arterial pressure (47). These results suggest that the ACE inhibitor fosinopril may neutralize the tendency of NSAIDs to increase blood pressure in thiazide-treated hypertensive patients. However, the design of this study precluded such a conclusion, since no evidence was provided that any of the NSAIDs increased blood pressure in the absence of fosinopril. Furthermore, the numbers were small and the precision of the comparison is likely to have been low. Careful monitoring of blood pressure is necessary when NSAIDs are introduced in thiazide-treated hypertensive patients, even when ACE inhibitors are co-prescribed. 

Thiazide diuretics do not stimulate or require prostaglandins to produce their desired effect and they do not directly interact with NSAIDs. The magnitude of increased risk of NSAID-induced AKI with concomitant triamterene cannot be estimated based on sporadic case reports [44]. 

Photoallergic reactions may occur as a result of exposure to systemically administered drugs such as griseofulvin, NSAIDs, phenothiazines, quinidine, sulfonamides, sulfonylureas, and thiazide diuretics as well as to external agents such as para-aminobenzoic acid (found in sunscreens), bithionol (used in soaps and cosmetics), paraphenylenediamine, and others. 

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