Zidovudine causes:
**Core Concept**
Zidovudine, also known as azidothymidine (AZT), is a nucleoside reverse transcriptase inhibitor (NRTI) used in the treatment of HIV/AIDS. It works by inhibiting the reverse transcriptase enzyme, which is essential for the replication of retroviruses like HIV.
**Why the Correct Answer is Right**
Zidovudine is a thymidine analog that competes with natural thymidine for incorporation into viral DNA, thereby terminating the elongation of the viral DNA chain. This leads to the inhibition of viral replication and ultimately, a decrease in the viral load. The correct answer is a consequence of this mechanism of action.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is not relevant to the mechanism of action of zidovudine.
**Option B:** This option is incorrect because zidovudine does not cause myelosuppression as a primary effect, although it can cause bone marrow suppression as a side effect.
**Option C:** This option is not accurate, as zidovudine is not a protease inhibitor.
**Clinical Pearl / High-Yield Fact**
Zidovudine is often used in combination with other antiretroviral medications to achieve a synergistic effect and reduce the development of resistance.
**Correct Answer:** B. Bone marrow suppression