They are designed to cause less side effects in patients than the more common non-steroidal anti-inflammatory drugs (NSAIDS).

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Celebrex treats pain as well as other NSAIDS, or non-steroidal anti-inflammatory drugs, such as ibuprofen, naproxen and aspirin.

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Prescriptions for non-steroidal anti-inflammatory drugs in Denmark are for relatively large doses, equivalent to 400mg or 600mg of ibuprofen.

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In a statement handed out to reporters, Merck said that the class effect might extend beyond these Cox-2 inhibitors, to many older non-steroidal anti-inflammatory drugs.

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These compounds, by virtue of their mode of action, were deemed to be as potent arthritis pain relievers as traditional non-steroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen and naproxen, but were believed to be safer than NSAIDs since they caused less gastrointestinal distress.

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