Acetaminophen is notably toxic to which two organs due to radical injury?

Acetaminophen (also known as paracetamol) is primarily known to cause hepatotoxicity, which is injury to the liver. When taken in overdose, acetaminophen is metabolized into a toxic metabolite (N-acetyl-p-benzoquinone imine, or NAPQI) that depletes glutathione stores and results in oxidative stress and cellular injury in the liver. This is why liver damage is one of the most critical consequences of acetaminophen overdose.

The kidney is also susceptible to acetaminophen toxicity, although to a lesser extent compared to the liver. Renal injury can occur primarily due to ischemic or nephrotoxic effects of the metabolites, particularly after significant liver damage as the kidney can be affected by the circulating toxic metabolites as well.

The combination of the liver and kidney represents a significant impact of acetaminophen toxicity due to their roles in metabolism and excretion of the drug and its metabolites. Other organs, like the heart, brain, lungs, or spleen, do not have the same level of susceptibility to the radical injury caused by acetaminophen. Thus, the correct answer highlights the two organs most notoriously involved in acetaminophen toxicity: the liver and the kidney.