Oxidized intracellularly to leukomethylene blue by NADPH-methemoglobin reductase, then reduces ferric (Fe3+) methemoglobin back to functional ferrous (Fe2+) hemoglobin. Also has antiseptic and antioxidant properties.
At a glance
Class
Methemoglobin Reductase Activator / Antidote
Storage
Store at room temperature; protect from light and heat
Dosing
Treatment for methemoglobinemia (acetaminophen toxicity in dogs, nitrate/nitrite
Route
IV (slow, diluted to 1%)
Frequency
Repeat once if needed; do not exceed 4 mg/kg total
NEVER use methylene blue in cats
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.
Find a vet near you →Safety
Methemoglobin level (co-oximetry)PCV/hematocrit (hemolysis)SpO2 (pulse oximetry unreliable with methemoglobin)Clinical color normalization
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.
Find a vet near you →Interactions
No documented interactions.
FAQs
Frequently asked questions
›What is Methylene Blue?
Methylene Blue is a methemoglobin reductase activator / antidote used in pets. Oxidized intracellularly to leukomethylene blue by NADPH-methemoglobin reductase, then reduces ferric (Fe3+) methemoglobin back to functional ferrous (Fe2+) hemoglobin. Also has antiseptic and antioxidant properties.
›What is Methylene Blue used for in pets?
Methylene Blue is used in veterinary medicine for: Treatment for methemoglobinemia (acetaminophen toxicity in dogs, nitrate/nitrite; NEVER use methylene blue in cats.
›What is the Methylene Blue dose for dogs?
For dogs, Methylene Blue is typically dosed as follows — Treatment for methemoglobinemia (acetaminophen toxicity in dogs, nitrate/nitrite: 1–1.5 mg/kg IV (slow/diluted to 1%) Repeat once if needed; do not exceed 4 mg/kg total. Always consult your veterinarian for a dose tailored to your pet's weight, age, and condition.
›What is the Methylene Blue dose for cats?
For cats, Methylene Blue is typically dosed as follows — NEVER use methylene blue in cats: undefined undefined N/A N/A. Always consult your veterinarian for a dose tailored to your pet's weight, age, and condition.
›Does Methylene Blue need a prescription?
Yes. Methylene Blue is a prescription medication and should only be administered under veterinary supervision.
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.
Find a vet near you →References
CDSCO approvals (India) — 1
New Chemical Disinfectant of Didycyl Dimethyl Ammonium Chloride Alkyl Dimethyl B
M/s Venkateshwara B.V Biocorp Pvt. Ltd., · Approved 25.06.2024
For Disinfection of inanimate /non living surface in poultry farms / hatcheries/ livestock farms.
Source: CDSCO Veterinary Drug Approval Registry (1969–2026)
References
The PetCare.AI drug reference is built from 13 authoritative sources cited across 580 drug monographs.
Textbooks & handbooks — 5
- Plumb's Veterinary Drug Handbook
- Withrow & MacEwen's Small Animal Clinical Oncology
- Merck Veterinary Manual
- NRC Nutrient Requirements of Dogs and Cats
- Veterinary Pharmacology and Therapeutics (Riviere & Papich)
Clinical guidelines & consensus — 4
- ASPCA Animal Poison Control Center Guidelines
- AAHA Diabetes Management Guidelines
- ASPCA Poison Control Guidelines
- RECOVER CPR Guidelines
Journals & peer-reviewed studies — 2
- EPIC Study (J Vet Intern Med 2016)
- JVIM FAT CAT Study
Regulatory & approvals — 1
- CDSCO Veterinary Drug Approval Registry (1969–2026)
Databases — 1
- Washington State University VCPL MDR1 Database