The anti-inflammatory drug Vioxx has been in the news for the wrong reasons and now scientists seem to have more clarity regarding Vioxx and the causative agent of the side-effects. The answer hovers around the vital property of the drug - the blood clotting mechanism, British scientists reveal.
These drugs known as COX-2 inhibitors are most often used to alleviate pain in chronic conditions like arthritis. The drugs achieve its purpose by hampering the function of the COX-2 enzyme, present in the inflamed areas. The medications also halt the COX-1 enzyme, found in the lining of blood vessels.
In 2004, Vioxx was recalled from the market due to perceived health risks. Prof. Jane Mitchell from the National Heart and Lung Institute at Imperial College London and her colleagues are of the opinion that blocking the COX-1 enzyme may result in clotting of blood. And, if the drugs are consumed in regular doses, this could enhance the risk of stroke or heart attack.
'Our new research is exciting because it means we can work on developing better COX-2 inhibitors that don't pose the same risks in terms of heart attacks and strokes,' Mitchell said.
Researchers had all along believed that COX-2 inhibitors caused the blockage of the COX-2 enzyme in the endothelium, triggering the adverse reaction. This study has lent a valuable insight, which is the absence of COX-2 enzyme in the endothelium and the presence of COX-1 enzyme, which is the reason behind the adverse side-effect. Impediments to the COX-1 enzyme could result in clots, that may trigger the adverse reaction, scientists said.