MOPP is a chemotherapy regimen for the treatment of Hodgkin's disease. It was the first successful multi-pharmaceutical therapy for the treatment of cancer. It is named for the four pharmaceuticals used in combination - mustargen, oncovin, procarbazine and prednisone. It is rarely used now as more effective therapies have been developed. However, it is still used for cases where the patient relapses, or where the patient has conditions that rule out other multi-drug regimens, such as allergies, lung problems or heart problems.