Dynacirc® (isradipine) is a medication used for high blood pressure treatment. It belongs to a group of medications known as calcium channel blockers. The medication was originally manufactured by Reliant Pharmaceuticals. However, the patents for all Dynacirc products have expired, and Dynacirc is now available in generic form. In fact, brand-name Dynacirc is no longer being made. A long-acting form, Dynacirc CR®, is still available (see Generic Dynacirc CR).