Retrospective evaluation of methionine intoxication associated with urinary acidifying products in dogs: 1,525 cases (2001-2012)

J Vet Emerg Crit Care (San Antonio). 2015 Sep-Oct;25(5):640-5. doi: 10.1111/vec.12343. Epub 2015 Jul 21.


Objective: To describe the signalment, clinical findings, timing of signs, outcome, and prognosis in a population of dogs exposed to methionine through the ingestion of urine acidifying products.

Design: Retrospective observational study from January 1, 2001 to December 31, 2012.

Setting: Animal Poison Control Center.

Animals: A total of 1,197 case calls yielding 1,525 dogs identified with presumed methionine ingestion.

Interventions: None.

Measurements and main results: Records of dogs with presumptive methionine ingestion were reviewed from the American Society for the Prevention of Cruelty to Animals Animal Poison Control Center database. Ingested methionine doses ranged from 3.9 mg/kg to 23,462 mg/kg. Clinical signs developed in 47% of dogs. The most common clinical signs were gastrointestinal (GI) and neurologic. The mean onset of GI signs was 2.8 hours following ingestion. The mean onset of neurologic signs was 6.8 hours following ingestion. GI signs were identified with ingested doses ≥22.5 mg/kg. Vomiting was the most common GI sign. Neurologic signs were identified with ingested doses ≥94.6 mg/kg. Ataxia was the most common neurologic sign. Resolution of clinical signs occurred within 48 hours of ingestion, and no fatalities were reported.

Conclusions: Prognosis for dogs with methionine intoxication is excellent. Vomiting and ataxia were the most common clinical signs associated with methionine toxicosis.

Keywords: gastrointestinal tract; intoxication; toxicology; toxins; treatment.

MeSH terms

  • Animals
  • Central Nervous System Diseases / chemically induced
  • Central Nervous System Diseases / veterinary*
  • Dog Diseases / chemically induced*
  • Dog Diseases / epidemiology
  • Dogs
  • Female
  • Gastrointestinal Diseases / chemically induced
  • Gastrointestinal Diseases / veterinary*
  • Male
  • Methionine / toxicity*
  • Retrospective Studies
  • Urine / chemistry


  • Methionine