Oxaliplatin injection is a chemotherapy drug used to treat certain types of cancer, such as colon cancer, rectal cancer, and other types of intestinal cancers. It is usually given intravenously (into a vein) along with other chemotherapy drugs. Oxaliplatin injection works by interfering with the growth of cancer cells, which prevents them from multiplying. It is usually given in cycles, which may last up to six months. Side effects can include nausea, vomiting, diarrhea, constipation, and fatigue.