OTC Pain Relievers and Fever Reducers (cont.)

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Side effects of aspirin

Aspirin prevents platelets from their natural ability to stick together and form blood clots. On the one hand, this effect can be used beneficially, such as to prevent the blood clots that cause heart attacks or strokes. On the other hand, by preventing blood clots, aspirin can have the detrimental effect of promoting bleeding. Therefore, aspirin should not be used by people who have diseases that cause bleeding (such as hemophilia and severe liver disease) or diseases in which bleeding may occur as a complication (such as stomach ulcers). Moreover, since the effect of aspirin on platelets lasts for many days, people should not take aspirin for at least seven days before surgical or dental procedures because of the increased risk of bleeding after the procedures.

In patients at risk for bleeding, acetaminophen can be an excellent alternative to aspirin since acetaminophen does not have an effect on platelets, blood clots, or bleeding.

Like aspirin, other NSAIDs affect platelets, but the duration of the effect is less than with aspirin. Two aspirin-related, salicylate-containing products (salsalate and choline magnesium trisalicylate) have no effect on the platelets, but they are available only by prescription.

Serious side effects of aspirin occur infrequently. However, they may occur and generally tend to be more frequent with higher doses. Therefore, it is advisable to use the lowest effective dose to minimize side effects.

The most common side effects of aspirin involve the gastrointestinal system. Aspirin can cause ulcers of the stomach and duodenum (first part of the small intestine), abdominal pain, nausea, gastritis (inflammation of the stomach), and even serious gastrointestinal bleeding from ulcers. Sometimes, ulcers of the stomach and bleeding occur without any abdominal pain, and the only signs of bleeding may be bloody or dark stools or weakness.

Although many people claim to be "allergic" to aspirin, most describe their "allergy" as abdominal pain or heartburn. These common side effects are not allergies, but rather reflect the irritating effects of aspirin on the lining of the stomach. True allergy to aspirin is a rare and serious condition in which a patient can develop swelling of tissues, spasm of the airways (bronchospasm) that causes difficulty breathing, and even anaphylaxis, a life-threatening condition. Clearly, patients with a history of allergy to aspirin should not take aspirin. Since aspirin is related chemically to the other NSAIDs, patients who are allergic to the other NSAIDs, such as ibuprofen (Motrin) and naproxen (Aleve), should also not take aspirin.

Report Problems to the Food and Drug Administration

You are encouraged to report negative side effects of prescription drugs to the FDA. Visit the FDA MedWatch website or call 1-800-FDA-1088.

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