Which of the following drugs is used to prevent HIV transmission from an HIV positive pregnant mother to child
**Core Concept**
The prevention of mother-to-child transmission (PMTCT) of HIV involves the use of antiretroviral therapy (ART) to reduce the viral load in the mother, thereby minimizing the risk of transmission to the child. This concept is crucial in the management of HIV-positive pregnant women.
**Why the Correct Answer is Right**
The correct answer is **Zidovudine (AZT)**, which is a nucleoside reverse transcriptase inhibitor (NRTI). Zidovudine is used in combination with other antiretroviral agents to prevent mother-to-child transmission of HIV. It works by inhibiting the reverse transcription of viral RNA into DNA, thereby reducing the viral load in the mother and minimizing the risk of transmission to the child. The use of zidovudine is recommended by the World Health Organization (WHO) and the Centers for Disease Control and Prevention (CDC) as part of the PMTCT guidelines.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect as there is no commonly used antiretroviral drug by this name in the context of PMTCT.
**Option B:** This option is incorrect as Nevirapine is used in some PMTCT regimens, but it is not the primary choice for preventing HIV transmission from mother to child.
**Option C:** This option is incorrect as Efavirenz is a non-nucleoside reverse transcriptase inhibitor (NNRTI) used in combination with other antiretroviral agents for the treatment of HIV, but it is not the primary choice for preventing HIV transmission from mother to child.
**Clinical Pearl / High-Yield Fact**
Zidovudine is administered to the mother in the third trimester of pregnancy, and a single dose of zidovudine is also given to the newborn within 72 hours of birth to further reduce the risk of HIV transmission.
**Correct Answer:** Zidovudine (AZT)