What is the biggest disadvantage of IV administration?

What is the biggest disadvantage of IV administration?

• A. Once a drug is given IV, it cannot be removed, risk of toxicity.
• B. There is no lag time (unlike oral).
• C. Embolism.
• D. Bacteria or subcutaneous tissue infiltration.

Answer: (A)

The main issue with IV administration is that the drug enters the bloodstream directly and immediately, with no absorption step to temper its delivery. Once it's in the circulation, you can’t really “undo” the exposure if toxicity or an adverse reaction occurs. Stopping the infusion stops more drug from entering, but the already circulating drug must be cleared by the body's elimination processes, which takes time. For medicines with a narrow therapeutic index or serious toxicity risk, this lack of reversibility makes IV delivery especially risky. Other listed concerns are real, but they’re specific complications or advantages rather than the fundamental drawback. Embolism and tissue infiltration are significant risks, and the absence of lag time is actually an advantage in achieving rapid effect, not a disadvantage.

The main issue with IV administration is that the drug enters the bloodstream directly and immediately, with no absorption step to temper its delivery. Once it's in the circulation, you can’t really “undo” the exposure if toxicity or an adverse reaction occurs. Stopping the infusion stops more drug from entering, but the already circulating drug must be cleared by the body's elimination processes, which takes time. For medicines with a narrow therapeutic index or serious toxicity risk, this lack of reversibility makes IV delivery especially risky.

Other listed concerns are real, but they’re specific complications or advantages rather than the fundamental drawback. Embolism and tissue infiltration are significant risks, and the absence of lag time is actually an advantage in achieving rapid effect, not a disadvantage.