Inhibits 11-beta-hydroxylase, the enzyme catalyzing the final step of cortisol synthesis (11-deoxycortisol → cortisol). Used diagnostically to test pituitary ACTH reserve and therapeutically to reduce cortisol in Cushing's syndrome.
At a glance
Class
Adrenal Steroidogenesis Inhibitor (Diagnostic/Therapeutic)
Storage
Store at room temperature, protect from light and moisture
Dosing
Rarely used therapeutically — trilostane and mitotane preferred for Cushing's
Frequency
q12h (therapeutic); once (diagnostic)
Safety
Cortisol levelsACTH11-deoxycortisolElectrolytesBlood pressure
Interactions
No documented interactions.
FAQs
Frequently asked questions
›What is Metyrapone?
Metyrapone is a adrenal steroidogenesis inhibitor (diagnostic/therapeutic) used in pets. Inhibits 11-beta-hydroxylase, the enzyme catalyzing the final step of cortisol synthesis (11-deoxycortisol → cortisol). Used diagnostically to test pituitary ACTH reserve and therapeutically to reduce cortisol in Cushing's syndrome.
›What is Metyrapone used for in pets?
Metyrapone is used in veterinary medicine for: Rarely used therapeutically — trilostane and mitotane preferred for Cushing's; Very limited feline data.
›What is the Metyrapone dose for dogs?
For dogs, Metyrapone is typically dosed as follows — Rarely used therapeutically — trilostane and mitotane preferred for Cushing's: undefined undefined PO q12h (therapeutic); once (diagnostic). Always consult your veterinarian for a dose tailored to your pet's weight, age, and condition.
›What is the Metyrapone dose for cats?
For cats, Metyrapone is typically dosed as follows — Very limited feline data: undefined undefined PO q12h. Always consult your veterinarian for a dose tailored to your pet's weight, age, and condition.
›Does Metyrapone need a prescription?
Yes. Metyrapone is a prescription medication and should only be administered under veterinary supervision.
References
References
Textbooks & handbooks
- Plumb, D.C. Plumb's Veterinary Drug Handbook. 10th ed., Wiley-Blackwell, 2023.
- Vail, D.M., Thamm, D.H., & Liptak, J.M. (eds.). Withrow & MacEwen's Small Animal Clinical Oncology. 6th ed., Saunders/Elsevier, 2020.
- Riviere, J.E., & Papich, M.G. (eds.). Veterinary Pharmacology and Therapeutics. 10th ed., Wiley-Blackwell, 2018.
- National Research Council. Nutrient Requirements of Dogs and Cats. National Academies Press, Washington DC, 2006.
- The Merck Veterinary Manual. Merck & Co., Online edition. https://www.merckvetmanual.com/
Clinical guidelines & consensus
- Fletcher, D.J., Boller, M., Brainard, B.M., et al. "RECOVER Evidence and Knowledge Gap Analysis on Veterinary CPR." Journal of Veterinary Emergency and Critical Care, 2012;22(S1):S102–S131.
- American Animal Hospital Association. 2018 AAHA Diabetes Management Guidelines for Dogs and Cats. AAHA Press.
Journals & peer-reviewed studies
- Hogan, D.F., Fox, P.R., Jacob, K., et al. "Secondary prevention of cardiogenic arterial thromboembolism in the cat: The FAT CAT study." Journal of Veterinary Cardiology, 2015;17(Suppl 1):S306–S317.
- Boswood, A., Häggström, J., Gordon, S.G., et al. "Effect of Pimobendan in Dogs with Preclinical Myxomatous Mitral Valve Disease and Cardiomegaly: The EPIC Study — A Randomized Clinical Trial." Journal of Veterinary Internal Medicine, 2016;30(6):1765–1779.
- ASPCA Animal Poison Control Center. Toxicology and Poison Management Guidelines. American Society for the Prevention of Cruelty to Animals. https://www.aspca.org/pet-care/animal-poison-control
Regulatory & approvals
- Central Drugs Standard Control Organisation (CDSCO), Government of India. Veterinary Drug Approval Registry, 1969–2026. Directorate General of Health Services. https://cdsco.gov.in/
Databases
- Washington State University, College of Veterinary Medicine. Veterinary Clinical Pharmacology Laboratory (VCPL) — MDR1 Multidrug Sensitivity Database. https://vcpl.vetmed.wsu.edu/
Educational reference only
This information is provided for educational purposes and is not a substitute for professional veterinary advice, diagnosis, or treatment. Always consult a qualified veterinarian before administering any medication to your pet.
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