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CLASS Study and COX-2 Drug Side Effects


This page describes the CLASS study and the side effects provided by COX-2 pain reliever drugs, focusing on the drug Celebrex. A number of studies have been conducted to evaluate COX-2 pain relievers.

In the late 1990s, CLASS (Celecoxib Long-term Arthritis Safety Study) engaged 8059 patients to evaluate gastrointestinal events and other adverse effects in those taking drugs similar to Vioxx: celecoxib (Celebrex) vs. ibuprofen (Advil), a traditional, non-selective pain reliever*.

The CLASS study found that those taking Celebrex were as likely to have cardiovascular side effects as patients taking a traditional pain reliever, such as ibuprofen. In other words, this study found no increase in side effects related to heart attack or stroke due to taking Celebrex, a COX-2 drug. The study also indicated that COX-2 inhibitors reduced pain, ulcers and other stomach problems caused by the traditional, ibuprofen type of pain relievers. The study report contained no indication of whether other COX-2 inhibitors, such as Vioxx,  could cause any potentially harmful cardiovascular side effects.

However, not all COX-2 inhibitors are the same. Apparently, celecoxib is a much weaker drug, when compared to other COX-2 inhibitors. Physiology studies indicate that Vioxx is about 9 times more potent than Celebrex in terms of blocking of the COX-2 enzymes. (Find out more aboutCOX enzymes and COX-2 inhibitors.)

Celecoxib is a COX-2 inhibitor drug marketed by Pfizer in the United States under the trade name of Celebrex. Recent government- and manufacturer-led studies, unveiled in late 2004, found that both Celebrex and Bextra, another COX-2 inhibitor, may also induce myocardial infarction and cardiovascular side effects. The reported side effects are under intense investigation, but neither Celebrex nor Bextra have been recalled from the market. Pfizer plans to continue marketing the drug to doctors, but has stopped consumer advertising for the pain reliever.

Visual Side Effects from Drugs

A common side effect from drugs is protein build-up in the lenses of the eyes. When the protein build-up is substantial enough to make the eye cloudy, this condition is called cataracts. This clouding of the lens can block vision and, if left untreated, lead to total blindness. In the United States, the cataract surgery operation is used to treat this condition and it is a very successful procedure. Indeed, new developments in cataract surgery have lead to a combination procedure that can treat both cataracts and the presbyopia condition at the same time. This procedure is called premium cataract surgery and patients are often able to function completely without glasses, either for distance vision or reading vision, after surgery. The Class study did not show any type of visual side effects associated with COX-2 inhibitor use, but they are common with other drugs.

If You Have Been Injured with Vioxx – Contact an Attorney

If you have been taking Vioxx, Celebrex, Bextra or similar Cox-2 inhibitors and have developed cardiovascular problems as a result, contact a personal injury lawyer to discuss your situation and find out if remuneration might be available. In addition, consult an experienced attorney if you suspect that the death of your loved one was caused by one of these drugs. If it can be proved that drug manufacturers acted negligently, you might be able to hold them responsible through a wrongful death lawsuit. If the deceased is survived by young children, a consultation with a knowledgeable family lawyer might also be necessary to resolve custody and child support issues. Sometimes it is best to contact a lawyer whose offices are in close proximity, as you may have to visit his or her offices on a periodic basis.

*Traditional pain relievers inhibit both COX-2 and COX-1 enzymes, which act to protect stomach lining.

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