Cumulative toxicity is the progressive development or worsening of adverse effects following repeated or prolonged exposure to a drug or other agent, when toxic effects accumulate over time because exposure exceeds the body’s capacity to eliminate the substance or repair the resulting damage. Accumulation may occur through retention of the drug or its metabolites, repeated injury to susceptible tissues, or the combined toxic effects of multiple medicines with similar pharmacological properties.
Cumulative toxicity is influenced by factors such as dose, duration of treatment, dosing interval, patient age, organ function (particularly renal and hepatic function), and concomitant medications. Recognizing cumulative toxicity is especially important during long-term antimicrobial therapy, where ongoing monitoring and dose adjustment may be required to minimize toxicity while maintaining therapeutic efficacy.
See also Toxicity, chronic