MDose · Veterinary drug reference
METHYLENE BLUE
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Source overview
Recorded excerpts for one species. Each dose remains a separate source entry; no regimen is selected.
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View full clinical evidence and sources ↓Clinical evidence
Pending clinical review (PROPOSED)Rule-based (RULE_BASED)— applies to the facts and dose entries in this species selection; individual source records retain their own status.
Indications3
Methemoglobinemia from oxidative toxins (acetaminophen, phenol, nitrates/chlorates); cyanide toxicity adjunct
DogExtra-label (EXTRA_LABEL)1 source record · View provenance
- Dog · Plumb's Veterinary Drug Handbook, 7th ed., p. 811–812 — Indications table · Not applicable · Extra-label (EXTRA_LABEL) · Pending clinical review (PROPOSED) · Rule-based
Original excerpt: Methemoglobinemia from oxidative toxins (acetaminophen, phenol, nitrates/chlorates); cyanide toxicity adjunct — Extra-label (human/livestock product)
- Dog · Plumb's Veterinary Drug Handbook, 7th ed., p. 811–812 — Indications table · Not applicable · Extra-label (EXTRA_LABEL) · Pending clinical review (PROPOSED) · Rule-based
Intraoperative staining of pancreatic islet-cell tumors
DogExtra-label (EXTRA_LABEL)1 source record · View provenance
- Dog · Plumb's Veterinary Drug Handbook, 7th ed., p. 811–812 — Indications table · Not applicable · Extra-label (EXTRA_LABEL) · Pending clinical review (PROPOSED) · Rule-based
Original excerpt: Intraoperative staining of pancreatic islet-cell tumors — Extra-label
- Dog · Plumb's Veterinary Drug Handbook, 7th ed., p. 811–812 — Indications table · Not applicable · Extra-label (EXTRA_LABEL) · Pending clinical review (PROPOSED) · Rule-based
Methemoglobinemia — last-resort single low dose only (most clinicians contraindicate)
CatExtra-label (EXTRA_LABEL)1 source record · View provenance
- Cat · Plumb's Veterinary Drug Handbook, 7th ed., p. 811–812 — Indications table · Not applicable · Extra-label (EXTRA_LABEL) · Pending clinical review (PROPOSED) · Rule-based
Original excerpt: Methemoglobinemia — last-resort single low dose only (most clinicians contraindicate) — Extra-label; high risk
- Cat · Plumb's Veterinary Drug Handbook, 7th ed., p. 811–812 — Indications table · Not applicable · Extra-label (EXTRA_LABEL) · Pending clinical review (PROPOSED) · Rule-based
Dose regimens4
This calculator performs arithmetic only on the sourced dosing field shown for each result — it does not verify the field's accuracy, does not select which field to use for a patient, and does not replace a veterinarian's order. Not for clinical use. Confirm every result against the primary source before dispensing.
Choose one species above to view its dose calculator.
Adverse effects5
Heinz body anemia, RBC morphologic changes, ↓ RBC lifespan — The dose-limiting toxicity
DogCatHorseNot applicable (NOT_APPLICABLE)3 source records · View provenance
- Dog · Plumb's Veterinary Drug Handbook, 7th ed., p. 811–812 — Side Effects / Adverse Effects table · Not applicable · Not applicable (NOT_APPLICABLE) · Pending clinical review (PROPOSED) · Rule-based
- Cat · Plumb's Veterinary Drug Handbook, 7th ed., p. 811–812 — Side Effects / Adverse Effects table · Not applicable · Not applicable (NOT_APPLICABLE) · Pending clinical review (PROPOSED) · Rule-based
- Horse · Plumb's Veterinary Drug Handbook, 7th ed., p. 811–812 — Side Effects / Adverse Effects table · Not applicable · Not applicable (NOT_APPLICABLE) · Pending clinical review (PROPOSED) · Rule-based
Drug-induced methemoglobinemia — Overdose paradox
Other speciesNot applicable (NOT_APPLICABLE)1 source record · View provenance
- Other species · Plumb's Veterinary Drug Handbook, 7th ed., p. 811–812 — Side Effects / Adverse Effects table · Not applicable · Not applicable (NOT_APPLICABLE) · Pending clinical review (PROPOSED) · Rule-based
Urine/secretion staining (blue-green) — Expected
Other speciesNot applicable (NOT_APPLICABLE)1 source record · View provenance
- Other species · Plumb's Veterinary Drug Handbook, 7th ed., p. 811–812 — Side Effects / Adverse Effects table · Not applicable · Not applicable (NOT_APPLICABLE) · Pending clinical review (PROPOSED) · Rule-based
Monitoring1
Methemoglobin % (response within 30 min), PCV daily × 3 days (Heinz bodies), urine color
Species not recordedNot applicable (NOT_APPLICABLE)1 source record · View provenance
- Species not recorded · Plumb's Veterinary Drug Handbook, 7th ed., p. 811–812 — Monitoring Parameters · Not applicable · Not applicable (NOT_APPLICABLE) · Pending clinical review (PROPOSED) · Rule-based
Contraindications1
Cats (consensus of most clinicians); renal insufficiency; hypersensitivity; intrathecal route; lactating dairy animals
Species not recordedNot applicable (NOT_APPLICABLE)1 source record · View provenance
- Species not recorded · Plumb's Veterinary Drug Handbook, 7th ed., p. 811–812 — Contraindications & Warnings table · Not applicable · Not applicable (NOT_APPLICABLE) · Pending clinical review (PROPOSED) · Rule-based
Precautions4
Repeat dosing escalates Heinz risk — check hematocrit for 3 days post-treatment; relatively ineffective in horses
Species not recordedNot applicable (NOT_APPLICABLE)1 source record · View provenance
- Species not recorded · Plumb's Veterinary Drug Handbook, 7th ed., p. 811–812 — Contraindications & Warnings table · Not applicable · Not applicable (NOT_APPLICABLE) · Pending clinical review (PROPOSED) · Rule-based
The antidote that can cause the disease: low dose reduces metHb, high dose oxidizes Hb — respect the 1 mg/kg canine / 1–1.5 mg/kg single-dose feline line.
Species not recordedNot applicable (NOT_APPLICABLE)1 source record · View provenance
- Species not recorded · Plumb's Veterinary Drug Handbook, 7th ed., p. 811–812 — Clinical pearl · Not applicable · Not applicable (NOT_APPLICABLE) · Pending clinical review (PROPOSED) · Rule-based
In feline acetaminophen toxicity, NAC + ascorbic acid carry the methemoglobinemia load; methylene blue is a desperate single-dose measure because cats' vulnerable hemoglobin makes the cure nearly as dangerous as the poison (Heinz bodies).
Species not recordedNot applicable (NOT_APPLICABLE)1 source record · View provenance
- Species not recorded · Plumb's Veterinary Drug Handbook, 7th ed., p. 811–812 — Clinical pearl · Not applicable · Not applicable (NOT_APPLICABLE) · Pending clinical review (PROPOSED) · Rule-based
Intraoperative insulinoma localization is the quirky second life of this dye (stains islet-cell tumors reddish-violet against dusky-blue pancreas).
Species not recordedNot applicable (NOT_APPLICABLE)1 source record · View provenance
- Species not recorded · Plumb's Veterinary Drug Handbook, 7th ed., p. 811–812 — Clinical pearl · Not applicable · Not applicable (NOT_APPLICABLE) · Pending clinical review (PROPOSED) · Rule-based
Interactions2
Serotonergic drugs (SSRIs etc. — human data) — Serotonin syndrome risk (MAO-A inhibition) — relevant to behavioral polypharmacy
Species not recordedNot applicable (NOT_APPLICABLE)1 source record · View provenance
- Species not recorded · Plumb's Veterinary Drug Handbook, 7th ed., p. 811–812 — Drug Interactions table · Not applicable · Not applicable (NOT_APPLICABLE) · Pending clinical review (PROPOSED) · Rule-based
Oxidizing agents — Working against each other (the disease mechanism)
Species not recordedNot applicable (NOT_APPLICABLE)1 source record · View provenance
- Species not recorded · Plumb's Veterinary Drug Handbook, 7th ed., p. 811–812 — Drug Interactions table · Not applicable · Not applicable (NOT_APPLICABLE) · Pending clinical review (PROPOSED) · Rule-based
Pharmacokinetics3
Mechanism — Reduced in tissues → leukomethylene blue donates electrons: metHb (Fe³⁺) → Hb (Fe²⁺)
Species not recordedNot applicable (NOT_APPLICABLE)1 source record · View provenance
- Species not recorded · Plumb's Veterinary Drug Handbook, 7th ed., p. 811–812 — Pharmacokinetics table · Not applicable · Not applicable (NOT_APPLICABLE) · Pending clinical review (PROPOSED) · Rule-based
Paradox — High doses OXIDIZE Hb → drug-induced methemoglobinemia
Other speciesNot applicable (NOT_APPLICABLE)1 source record · View provenance
- Other species · Plumb's Veterinary Drug Handbook, 7th ed., p. 811–812 — Pharmacokinetics table · Not applicable · Not applicable (NOT_APPLICABLE) · Pending clinical review (PROPOSED) · Rule-based
Elimination — Urine/bile (colorless metabolites); blue-green urine expected
Species not recordedNot applicable (NOT_APPLICABLE)1 source record · View provenance
- Species not recorded · Plumb's Veterinary Drug Handbook, 7th ed., p. 811–812 — Pharmacokinetics table · Not applicable · Not applicable (NOT_APPLICABLE) · Pending clinical review (PROPOSED) · Rule-based
Pregnancy / lactation considerations1
Human FDA category C; safety not demonstrated — antidotal use only.
Species not recordedNot applicable (NOT_APPLICABLE)1 source record · View provenance
- Species not recorded · Plumb's Veterinary Drug Handbook, 7th ed., p. 811–812 — Pregnancy & Lactation · Not applicable · Not applicable (NOT_APPLICABLE) · Pending clinical review (PROPOSED) · Rule-based
Literature references18
References are linked to this drug. Species applicability is not recorded here, so the species filter does not narrow this list. Imported dates do not retain their original precision; confirm dates in the original citation.
- A methylene blue based electrochemical assay to quantify haemoglobin in blood for point-of-care anaemia diagnosis.
Study summary not available in the imported record. Open the original citation to review the study.
- Efficacy of mechanical debridement with adjunct antimicrobial photodynamic therapy for the management of plaque-induced gingivitis in patients undergoing clear aligner therapy and fixed orthodontic therapy.
Study summary not available in the imported record. Open the original citation to review the study.
- Ultrasound-guided cranial multifidus cervicis plane block in dogs: a cadaveric study.
Study summary not available in the imported record. Open the original citation to review the study.
- Camel plasma as an innovative non-antibiotic therapy for Escherichia coli-induced colibacillosis in neonatal lambs: a comparative pilot study with antibiotics, camel milk, and probiotics under a One Health framework.
Study summary not available in the imported record. Open the original citation to review the study.
- Two-point rectus sheath block technique results in more extensive dye spread in the abdominal wall than one-point technique in dog cadavers.
Study summary not available in the imported record. Open the original citation to review the study.
Sources: PubMed, National Library of Medicine; Plumb DC. Plumb's Veterinary Drug Handbook. 7th ed. PharmaVet Inc; 2011.
Owner information handout
Plain-language medication information to review with the owner. Open the handout to print it or download a PDF.