Dose-dependent toxicity can be due to the pharmacologic action of a drug, a pathologic effect of a drug or metabolite, or genotoxicity. Which option best describes this toxicity type?

• A. Idiosyncratic toxicity
• B. Dose-dependent
• C. Acute toxicity due to overdose
• D. Drug-drug interaction toxicity

Answer: (B)

Dose-dependent toxicity means the harmful effects of a drug become more pronounced as the dose increases. This fits the description because the toxicity can arise from the drug’s pharmacologic action at higher exposure, from toxic metabolites formed with greater dose, or from genotoxic effects that accumulate with more exposure. In other words, the severity or likelihood of toxicity scales with how much drug is given.

Idiosyncratic toxicity is not dose-related; it occurs unpredictably in certain individuals. Acute toxicity due to overdose is a high-dose instance of dose-related harm but describes a specific scenario rather than the general principle. Drug-drug interaction toxicity arises from interactions between drugs rather than the dose-dependent mechanism of toxicity itself.