According to the birth watchdog group the March of Dimes, preventing birth defects from a widely used acne drug is too heavy a burden on doctors, patients and pharmacists.
Doctors say that the restrictions placed on Accutane and generic versions are so complex and time-consuming patients may well resort to the Internet, where counterfeit medicines may be accessed with little regard to safeguards to prevent pregnancy.
Accutane is a prescription medication used to treat severe acne that causes multiple inflamed cysts and scarring which has not responded to other treatments.
It is a member of a family of drugs called retinoids, which are related to vitamin A, and when taken during pregnancy, they can cause very serious birth defects or miscarriages.
At present Accutane is the only drug approved for the condition and several attempts have been made since its 1982 approval to prevent pregnancies among women taking the drug.
Before the drug was approved, testing had shown that it could cause fetal abnormalities in animals, and drug company Roche warned against its use by pregnant women, but pregnancies resulting in birth defects still occur.
According to the March of Dimes, more than 1,000 women have become pregnant while using Accutane.
Stricter measures on sales of the drug are due to take effect from March 1, but many dermatologists have already adhered to the restrictions.
Dr. Diane Thiboutot of the American Academy of Dermatology has apparently reported to the a U.S. Food and Drug Administration (FDA) advisory panel of the confusion and frustration experienced by pharmacists, doctors and patients and is seeking a delay of two months before the new program takes full effect.
The new plan means that patients, doctors, pharmacists and wholesalers must register with drug makers and must tell patients about risks.
Women of child-bearing age will be required to sign consent forms and undergo monthly pregnancy tests.
A computer system that verifies the safety steps have been followed, is hard to access via the Internet or phone.