Which condition can lead to a toxic level of medication in a patient?

Renal insufficiency can lead to toxic levels of medication in a patient because the kidneys play a critical role in the excretion of many drugs and their metabolites. When renal function is impaired, the ability of the body to clear medications is significantly reduced. As a result, drugs can accumulate in the bloodstream, leading to potentially toxic levels and increased risk of adverse effects.

In a healthy individual, the kidneys filter out waste products and excess substances, maintaining homeostasis within the body. However, in cases of renal insufficiency, this function is compromised, which means that drugs that are normally excreted can remain in the body longer than intended. It is essential for healthcare providers to monitor drug levels and adjust dosages accordingly in patients with renal impairment to avoid toxicity.

Other options, such as hepatic failure, also have the potential to affect drug metabolism and excretion, but renal insufficiency is a more direct cause of accumulation and toxicity for medications primarily cleared by the kidneys. Increased hydration could help support renal function by diluting urine, and a normal drug dosage would not inherently lead to toxicity if the elimination pathways are functioning correctly, making those options less relevant in this context.