Doxil is an antineoplastic antibiotic drug. It is a medication indicated for the treatment of different types of cancers. It is, in many cases, used in combination with a number of other drugs. Doxil works by simply killing off any cancer cells it encounters. Doxil is an intravenous drug that has to be administered in a hospital setting under strict supervision of a doctor or senior healthcare practitioner. It can cause serious and sometimes life threatening damage if it comes into contact with other cells.