From Dog

Methylphenidate (Ritalin) is an anti-ADHD medication used for children that can cause toxicosis in dogs.

This drug would have theoretical benefits in dogs with narcolepsy but side-effects outweigh the benefits compared with other drugs.

Accidental intoxication by dogs is relatively uncommon but has been reported, with symptoms occurring when doses >7.5 mg/kg have been consumed[1].

Clinical signs of methylphenidate toxicosis are related to sudden catecholamine release similar to that witnessed with amphetamine or pseudoephedrine toxicity[2].

Symptoms include hyperactivity, hyperthermia, tachycardia, tachypnea, and in severe cases, seizures and sudden death[3].

Severity of clinical signs was not strongly associated with dose. More severe and prolonged clinical signs are associated with ingestion of extended-release formulations[4].

Treatment usually involves intravenous fluid therapy and sedation with drugs such as acepromazine, diazepam or phenobarbital.

Severe intoxication may require induction of emesis with apomorphine followed by induction of general anesthesia and gastric lavage with activated charcoal.

Favourable outcomes have been reported in most cases.


  1. Bakhtiar R et al (2004) Toxicokinetic assessment of methylphenidate (Ritalin) in a 13-week oral toxicity study in dogs. Biomed Chromatogr 18(1):45-50
  2. Diniz PP et al (2003) Amphetamine poisoning in a dog: case report, literature review and veterinary medical perspectives. Vet Hum Toxicol 45(6):315-317
  3. Genovese DW et al (2010) Methylphenidate toxicosis in dogs: 128 cases (2001-2008). J Am Vet Med Assoc 237(12):1438-1443
  4. Lavy E et al (2011) Pharmacokinetics of methylphenidate after oral administration of immediate and sustained-release preparations in Beagle dogs. Vet J 189(3):336-340