Thalidomide is a sedative that used to be prescribed to treat anxiety, tension, gastritis and insomnia. It was also used to relieve morning sickness in pregnant women. However, thalidomide was found to cause deformity in children born to mothers who took the drug and it was withdrawn in the UK during the early 1960s.

Thalidomide caused birth defects across more than 46 nations and affected over 10,000 babies. These babies were born with missing or abnormal limbs, feet or hands. Other defects included abnormal or absent ears, heart and kidney problems, cleft palate, spinal cord defects and digestive system disorders.

Today, thalidomide is sold and prescribed as an anti-cancer therapy and as a treatment for patients with leprosy, HIV/AIDS, rheumatoid arthritis, sarcoidosis, Chron’s disease, various skin conditions and graft-versus-host disease.

Thalidomide is used to treat a complication of leprosy referred to as erythema nodosum leprosum (ENL). The main effect of this drug in the treatment of ENL is its fever reducing property and it has only been shown to have a limited effect in the control of neuritis, the main cause of disability in people with leprosy.

Thalidomide is given in combination with prednisolone and melphalan to treat myeloma in patients aged 65 or older who are not suitable for stem cell treatment. Researchers are still trying to elucidate the mechanism of this drug in treating myeloma but studies have shown that thalidomide can prevent the development of new blood vessels required to provide oxygen and nutrients to tumors. Without the formation of this new vasculature (angiogenesis), tumors cannot grow larger than the size of a pinhead. Drugs that work in this way are referred to as anti-angiogenics or angiogenesis inhibitors.