Thalidomide, << tha LIHD oh myd >> , is a drug that caused serious birth defects in babies born in the 1950’s and early 1960’s. In the most severe instances, babies were born missing arms and legs. Some babies were born with flipperlike arms and legs, a condition called phocomelia << foh coh MEEL yah >> . Other birth defects included missing or deformed ears, and abnormalities of the spinal cord, heart, and other organs. More than 12,000 babies were born with birth defects in 46 countries because of thalidomide.
Beginning in 1957, thalidomide was widely used throughout Germany, Canada, Japan, and other countries. Physicians prescribed the drug as a sedative and also gave it to pregnant women to relieve morning sickness. In the United States, the drug was not approved by the Food and Drug Administration (FDA) and was not sold. By 1960, physicians in several countries were shocked by a sudden increase in the number of babies born with severe birth defects. Researchers soon traced the birth defects to thalidomide. Scientists found that birth defects resulted if women had taken even a single dose of the drug during the first few months of pregnancy. The drug was banned worldwide in 1962.
Thalidomide causes birth defects by blocking angiogenesis << an jee oh JEHN uh sihs >> , the growth of new blood vessels in the body. New blood vessels are necessary for the development of arms and legs during the growth of a fetus. Scientists, however, think that thalidomide may be used for treating cancer tumors, which also require new blood vessels to grow. Thalidomide also blocks the action of tumor necrosis factor (TNF) alpha, a protein that causes inflammation, fever, weight loss, and other problems. Many diseases, such as leprosy (Hansen’s disease), tuberculosis, lupus, and AIDS, increase the level of TNF alpha in the body. Researchers have found thalidomide to be effective in treating symptoms of these diseases.
In 1998, the FDA approved thalidomide as a treatment for leprosy. The FDA established a special distribution system to ensure thalidomide is not taken by pregnant women. In this system, physicians must educate patients about the dangers of the drug. Pharmacists keep detailed records of how much thalidomide is dispensed. Patients must sign an agreement that they understand the risks of thalidomide and will not share the drug with other people. Women of childbearing age must prove that they are using birth control and have frequent pregnancy tests while taking the drug. With this system, scientists hope that thalidomide can be made available safely to the people who need it.
See also Angiogenesis .
