What is the DOCP dosing and electrolyte monitoring protocol for dogs with hypoadrenocorticism?

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Desoxycorticosterone pivalate (DOCP) should be started at 1.1–1.5 mg/kg SC or IM, not the manufacturer-labeled 2.2 mg/kg, with electrolytes rechecked at 10–14 days and again at 25 days after each injection to guide dose titration. The 2023 AAHA Selected Endocrinopathies Guidelines explicitly endorse 1.1–1.5 mg/kg as appropriate starting doses in most cases, citing evidence that the label dose is excessive for the majority of dogs.7 The case for lower starting doses is well-supported. Starting at 1.1 mg/kg q30d maintained mean serum sodium:potassium (Na:K) ratios ≥32 throughout a 90-day trial, with no dog developing electrolyte abnormalities requiring medical intervention.1 Starting at 1.5 mg/kg q30d controlled clinical signs and electrolytes in the majority of dogs, and no dog in that cohort ultimately required the 2.2 mg/kg label dose.2 Plasma renin activity (PRA) was overly suppressed on 80.8% of assessments in dogs receiving 2.2 mg/kg, compared to elevated PRA on only 20.5% of assessments in dogs receiving 1.1 mg/kg — indicating that the label dose produces biochemical overtreatment in most patients.1 PRA suppression in DOCP-treated dogs has been confirmed as a consistent finding, with only 18.2% of dogs in one cohort requiring the full 2.2 mg/kg dose.5 Dose titration is guided by serum electrolytes at 10–14 days and 25 days post-injection. If hyperkalemia or hyponatremia persist, the dose is increased. If electrolytes are normal, the dose is gradually decreased with continued monitoring.7 The median maintenance dose after starting at 1.5 mg/kg was 1.1 mg/kg (range 0.7–1.8 mg/kg), with dose reductions required in the majority of dogs after 2–3 months.2 Doses as low as 0.35 mg/kg have maintained electrolyte control in individual dogs.2 The dosing interval can be extended beyond 30 days in most dogs. The duration of action of DOCP in newly diagnosed dogs ranges from 32 to 94 days (median 62 days), and in previously treated dogs from 41 to 124 days (median 67 days).