Which drug is contraindicated due to its teratogenic effects?

Efavirenz is known to be contraindicated in pregnancy due to its teratogenic effects. Research has indicated that the use of efavirenz during the first trimester of pregnancy is associated with an increased risk of neural tube defects and other congenital anomalies. As a non-nucleoside reverse transcriptase inhibitor (NNRTI), efavirenz has the potential to affect fetal development, prompting health organizations to recommend alternative antiretroviral therapies that are considered safer during pregnancy.

In contrast, ritonavir, nevirapine, and atazanavir have been studied for their safety profile in pregnancy and are generally regarded as safer options. While there are cautionary notes regarding their use, they do not carry the same level of teratogenic risk as efavirenz. Therefore, efavirenz stands out as a medication that poses significant risks to fetal development, making its use contraindicated in pregnant individuals.