Cat · Felis catus · typical adult weight 2.50–7.00 kg
Vitamin D is dosed at 0.0015–0.0035 mcg/kg calcitriol PO q24h in cats, per Verified against Plumb's Veterinary Drug Handbook, 10th Ed, p.198 (2026-08-01). — Plumb's 10th ed (held) printed p.170-171 (corpus PDF p.197-198), Calcitriol monograph, Dosages [LOCATOR CORRECTED 2026-08-12 — the clause previously here named the Vitamin A monograph; this rule doses calcitriol]; page located 2026-08-05 from the book's own running heads, verified to name the drug in its body text. — SOURCE EDITION: Plumb's Veterinary Drug Handbook — ISBN 9781394172207, https://openlibrary.org/isbn/9781394172207 CORRECTED 2026-08-13: the served 0.02-0.03 mcg/kg is 20-30 ng/kg, roughly 10x the printed initial dose and 3-4.5x the printed ceiling. Plumb's 10th ed corpus p.198: "Recommended initial dosage: 1.5 - 3.5 ng/kg PO once daily, preferably in the evening on an empty stomach"; corpus p.199: "do not exceed 6.6 ng/kg/day unless also monitoring ionized calcium". Papich 5th ed corpus p.126: "2.5 ng/kg, PO, once daily". BSAVA corpus p.448: "calcitriol: 1.5-3.5 ng/kg p.o. q24h". The ~20 ng/kg figure that appears on Plumb's corpus p.199 is a PULSED-dosing strategy, not a daily dose. Calcitriol overdose causes hypercalcaemia and nephrocalcinosis in patients who already have chronic kidney disease.. Vitamin D is used in cats for CKD secondary hyperparathyroidism. Routes documented in cats: PO. A typical adult cat weighs 2.50–7.00 kg. ExoticRx lists 1 cited dose rule for Vitamin D in cats, drawn from published veterinary references. Verify against current literature before clinical use.
US trade names: Calcitriol, Cholecalciferol
| Route | Dose | Frequency | Duration | Indication | Evidence | Source |
|---|---|---|---|---|---|---|
| PO | 0.0015–0.0035 mcg/kg calcitriol | q24h | Long-term | CKD secondary hyperparathyroidism | Moderate | Verified against Plumb's Veterinary Drug Handbook, 10th Ed, p.198 (2026-08-01). — Plumb's 10th ed (held) printed p.170-171 (corpus PDF p.197-198), Calcitriol monograph, Dosages [LOCATOR CORRECTED 2026-08-12 — the clause previously here named the Vitamin A monograph; this rule doses calcitriol]; page located 2026-08-05 from the book's own running heads, verified to name the drug in its body text. — SOURCE EDITION: Plumb's Veterinary Drug Handbook — ISBN 9781394172207, https://openlibrary.org/isbn/9781394172207 CORRECTED 2026-08-13: the served 0.02-0.03 mcg/kg is 20-30 ng/kg, roughly 10x the printed initial dose and 3-4.5x the printed ceiling. Plumb's 10th ed corpus p.198: "Recommended initial dosage: 1.5 - 3.5 ng/kg PO once daily, preferably in the evening on an empty stomach"; corpus p.199: "do not exceed 6.6 ng/kg/day unless also monitoring ionized calcium". Papich 5th ed corpus p.126: "2.5 ng/kg, PO, once daily". BSAVA corpus p.448: "calcitriol: 1.5-3.5 ng/kg p.o. q24h". The ~20 ng/kg figure that appears on Plumb's corpus p.199 is a PULSED-dosing strategy, not a daily dose. Calcitriol overdose causes hypercalcaemia and nephrocalcinosis in patients who already have chronic kidney disease. |
Every held source for this drug and species, as printed. Where they differ, both are shown — the choice is yours, not ours.
| Dose (mcg/kg) | Route | Source | As printed |
|---|---|---|---|
| 0.03 | PO | BSAVA Small Animal Formulary, 10th ed — Part A (Canine and Feline)p.448 | 2.5-7.5 ng/kg p.o. q12h for maintenance; alfacalcidol: 0.01-0.03 μg (micrograms)/kg p.o. q24h and thereafter titrated to effect. |
Figures are transcribed from the cited page or table of each held edition and are shown for reference only. They are not dose recommendations, they do not feed the calculator, and none has been reviewed by a veterinarian.
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Active form (calcitriol) binds VDR promoting intestinal calcium and phosphorus absorption, bone mineralization, and parathyroid hormone regulation.
Calcitriol: used for renal secondary hyperparathyroidism and hypoparathyroidism. Narrow therapeutic index — hypercalcemia risk. Monitor ionized calcium frequently. Do not confuse calcitriol with cholecalciferol.
Species-specific contraindications and adverse-reaction reports for cats may differ from canine / feline reference data — consult the primary citations listed with each rule.
Vitamin D dose range in cats, with cited source references: PO 0.0015–0.0035 mcg/kg calcitriol q24h. Reference ranges from cited sources — verify against current literature before clinical use.
Documented routes for Vitamin D in cats: PO.
Cited course lengths for Vitamin D in cats include: Long-term. Duration depends on the indication — match it to the specific dose rule in the table above.
Vitamin D is indicated in cats for: CKD secondary hyperparathyroidism.
These are general warnings for Vitamin D across species; consult the cat dosing table above for species-specific guidance. Calcitriol: used for renal secondary hyperparathyroidism and hypoparathyroidism. Narrow therapeutic index — hypercalcemia risk. Monitor ionized calcium frequently. Do not confuse calcitriol with cholecalciferol.
Why a species-specific page? Vitamin D pharmacokinetics differ across species: dose ranges, intervals, and route preferences are not interchangeable. Cross-extrapolation from canine doses is unsafe in cats — the rules above are the citations specific to this species, not generic recommendations.
Sourced from published veterinary references; awaiting credentialed clinical reviewer. See our editorial process. Reference only — not veterinary advice.