Chemotherapy (chemo) is a breast cancer treatment that uses cancer-killing drugs. The drugs may be injected into a vein or given by mouth. Learn more about chemo.
More than 100 chemotherapy or chemo drugs are used to treat cancer – either alone or in combination with other drugs or treatments. These drugs are very different in their chemical composition, how they are taken, their usefulness in treating specific forms of cancer, and their side effects.
Chemo drugs kill fast-growing cells, but because these drugs travel throughout the body, they can affect normal, healthy cells that are fast-growing, too. Damage to healthy cells causes side effects.