Derived from Saccharopolyspora spinosa fermentation. Activates nicotinic acetylcholine receptors at a unique site, causing involuntary muscle contractions, paralysis, and death of fleas. Also activates GABA receptors at high concentrations.
At a glance
Class
Spinosyn Insecticide
Storage
Store at room temperature below 30°C
Dosing
FDA-approved oral flea treatment
FDA-approved for cats ≥14 weeks and ≥1
Safety
Flea burden assessmentGI tolerance (first dose)Seizure history
Interactions
No documented interactions.
Brands
Other markets
Trifexis (with milbemycin)
FAQs
Frequently asked questions
›What is Spinosad?
Spinosad is a spinosyn insecticide used in pets. Derived from Saccharopolyspora spinosa fermentation. Activates nicotinic acetylcholine receptors at a unique site, causing involuntary muscle contractions, paralysis, and death of fleas. Also activates GABA receptors at high concentrations.
›What is Spinosad used for in pets?
Spinosad is used in veterinary medicine for: FDA-approved oral flea treatment; FDA-approved for cats ≥14 weeks and ≥1.
›What is the Spinosad dose for dogs?
For dogs, Spinosad is typically dosed as follows — FDA-approved oral flea treatment: 30 mg/kg PO Monthly. Always consult your veterinarian for a dose tailored to your pet's weight, age, and condition.
›What is the Spinosad dose for cats?
For cats, Spinosad is typically dosed as follows — FDA-approved for cats ≥14 weeks and ≥1: 50 mg/kg PO Monthly. Always consult your veterinarian for a dose tailored to your pet's weight, age, and condition.
›Does Spinosad need a prescription?
Yes. Spinosad 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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