How should dosing be adjusted for medications in dogs with reduced renal function?

• A. Use higher doses or shorter intervals.
• B. Use lower doses or longer intervals, choose renally cleared alternatives when possible, and monitor renal function and drug levels.
• C. Dosing unchanged.
• D. Stop all medications.

Answer: (B)

When kidney function is reduced, the body clears many drugs more slowly, so the drug stays in the system longer and can build up to toxic levels. The best way to manage this is to adjust how you give the medicine: use a lower dose or space doses farther apart for drugs that are cleared by the kidneys. If possible, choose alternatives that are not primarily renally cleared. In all cases, monitor renal function (e.g., creatinine, BUN, hydration/urine output) and, for drugs with a narrow therapeutic window, check drug levels and adjust as needed. Stopping all medications or keeping the same dosing would either risk toxicity or fail to control the underlying condition.