Which medication should be avoided during pregnancy due to the risk of fetal defects?

Accutane, also known as isotretinoin, should be avoided during pregnancy due to its high potential for causing severe fetal defects. This medication is a powerful retinoid used primarily to treat severe acne that does not respond to other treatments. Isotretinoin is categorized as a Category X medication, which means that studies in animals or humans have demonstrated fetal abnormalities, and the risks involved in use during pregnancy clearly outweigh any possible benefits.

The mechanism of isotretinoin's teratogenic effects is believed to involve disruption in the development of various fetal structures, leading to significant defects, including craniofacial anomalies, cardiac defects, and neurological symptoms. For this reason, stringent pregnancy prevention programs, such as the iPLEDGE program in the United States, are enforced to ensure that women who are capable of becoming pregnant do not use this medication unless strict compliance with prevention measures is observed.

While other medications listed may have considerations regarding their use in pregnancy, they do not carry the same level of risk for teratogenic effects as isotretinoin, making it distinctly critical to avoid this medication during pregnant or potentially pregnant patients.