The Re-emergence of an Old Drug

Environmental factors that contribute to abnormal fetal growth and development are called teratogens. Included in this group are infectious agents, certain drugs or chemicals, maternal and metabolic factors.

Teratogenic exposures can affect the fetus in a number of ways including physical abnormalities or birth defects and abnormalities of the central nervous system. The timing of exposure, the dose or amount of exposure, and mother/fetal metabolisms are critical factors involved in teratogenic effects.

In the late 1950’s and early 1960’s a drug called thalidomide was marketed outside the United States to treat morning sickness during pregnancy and as an over-the-counter sedative. Its use by pregnant women resulted in the births of thousands of babies with major malformations between the years of 1958-1963. Primary abnormalities involved limbs, ears, eyes and the heart. Thalidomide was subsequently banned in the early 1960’s.

Thalidomide has recently re-emerged as a drug of interest, use, and investigation. In July 1998, the FDA approved the used of thalidomide in the treatment of Hansen’s disease, commonly known as leprosy. The drug is currently being investigated for use in the treatment of AIDS, tuberculosis, and as a chemotherapeutic agent in certain cancers.

Because of thalidomide’s role in causing severe birth defects, the FDA mandated strict regulations in its distribution and use. The oversight program is called S.T.E.P.S. and its purpose is to prevent fetal exposure. S.T.E.P.S. or A System for Thalidomide Education and Prescribing Safety stipulates six guidelines:


  • Required pregnancy testing before use of drug
  • Required birth control measures before, during and four weeks after drug use
  • Physician education
  • Patient education
  • 100% patient registry
  • Patient informed consent forms


This program represents a zero tolerance policy for thalidomide exposure during pregnancy. If there is ONE fetal exposure, the FDA will re-evaluate its distribution and use policies. If used with great care, thalidomide can bring much relief to those who suffer with the disfiguring effects of leprosy and spare needless injuries to developing babies.