Drug interactions: Ibuprofen may increase blood levels of digoxin (Lanoxin); however, it is unclear whether this interaction is important enough to recommend that patients taking digoxin not take ibuprofen.

NSAIDs reduce the blood pressure-lowering effects of certain high blood pressure (antihypertensive) medications, including: thiazide diuretics such as hydrochlorothiazide (Dyazide, Maxzide); beta-blockers such as propranolol or atenolol (Inderal, Tenormin), and metoprolol (Lopressor); angiotensin receptor antagonists such as enalapril (Vasotec), lisinopril (Zestril; Prinivil), benazepril (Lotensin), quinapril (Accupril), ramipril (Altace), and captopril (Capoten); and some medications that act on the brain, such as clonidine (Catapres).

NSAIDs can increase the levels of lithium in the blood, which can result in lithium-related side effects.

NSAIDs can also increase the levels of methotrexate in the blood and have been reported to result in methotrexate-related side effects.

What about overdoses of pain relievers and fever reducers?

The American Association of Poison Control Centers reported that of all overdoses of OTC products, 66% involved acetaminophen, 19% involved ibuprofen, and 15% involved aspirin. Aspirin overdose can occur with as little as 150 mg/kg (10,000mg or 10 grams in the average sized male) as a single dose, or 90 mg/kg per day for at least two consecutive days. Symptoms of toxicity due to aspirin may include tiredness, ringing in the ears, rapid breathing, seizures, vomiting, bleeding, and coma. Large doses of acetaminophen rarely cause serious problems in children. In adults, as little as 10 grams can damage the liver and the kidneys. Overdoses of ibuprofen rarely produce important problems. Nausea, vomiting, stomach pain, tiredness, and dizziness are the most common symptoms of large doses of ibuprofen. Rarely, coma may occur.

Reference: FDA Prescribing Information