Final Answer:
Metformin drugs should be discontinued 48 hours after administration of water-soluble iodinated contrast media thus option B is correct
Step-by-step explanation:
Contrast media used in medical imaging procedures, particularly water-soluble iodinated contrast media, can pose a risk of lactic acidosis when combined with certain medications. Metformin, an oral antidiabetic drug commonly used to manage diabetes, is one such medication that should be discontinued 48 hours after the administration of contrast media (option B).
When metformin is used alongside iodinated contrast agents, there is an increased risk of lactic acidosis, a serious condition that can be fatal. Lactic acidosis occurs due to the accumulation of lactic acid in the body, and the combination of metformin and contrast media can exacerbate this effect. To mitigate this risk, it is recommended to discontinue metformin for at least 48 hours before and after the administration of contrast media.
The rationale behind this recommendation lies in the renal clearance of metformin. Both metformin and iodinated contrast media are excreted through the kidneys, and their simultaneous presence can lead to impaired renal function and an increased risk of lactic acidosis. By allowing a 48-hour interval, the body has sufficient time to eliminate both the contrast media and metformin, reducing the risk of adverse effects.