Beta-blocker tablets. Blister packs of Cardivas, a beta-receptor blocking drug, or beta-blocker. Cardivas is used to treat chest pain (angina), lower blood pressure and correct abnormal heart rhythms (arrhythmia). Cardivas is a trade name for carvedilol, which works by selectively blocking the beta-receptors in the heart, lungs and other organs, inhibiting the effect of the hormones adrenaline and noradrenaline. The heart is able to beat more slowly and regularly, using less energy and requiring less oxygen. The pressure at which blood is pumped around the body is also lowered. Cardivas is made by Sun Pharmaceuticals Ltd.