Drug repurposing has been increasingly used by both researchers and clinicians to identify new cancer treatments. The alpha-1 adrenoreceptor blockers are a class of drugs that have been used for many years in the treatment of hypertension and benign prostatic hyperplasia. Some of the drugs in this class, notably the quinazoline derivatives, have been found to display cytotoxic properties, identifying them as potential options in the treatment of cancer. This review will examine the currently available evidence that investigates the cytotoxic and anti-cancer properties of these agents, the mechanisms behind these properties and how the alpha-1 blockers fit within current cancer therapies. It aims to answer the question of whether these agents can go from the laboratory bench top into cancer clinics.