The name and picture of the pet has been changed due to sensitive nature of the case.
Bailey, a young Yorkshire Terrier presented to the hospital for being lethargic and seemingly tired. He seemed like he was off balance and had fallen over a couple of times. He had been eating and drinking with no vomiting and diarrhea. He had been acting completely normal earlier in the day and was in the house and around the teenage son all day.
On physical exam Bailey was intermittently somnolent but became alert when interacted with. Otherwise his physical exam was normal.
Bailey’s physical exam was consistent with multiple disorders or diseases but the intermittent somnolence with alertness when stimulated and the history of falling over and acting tired were very suspicious for marijuana ingestion. Prior to conducting a metabolic work up requiring many different tests, we decided to test Bailey for marijuana intoxication by using a human drug test requiring urine. The test we used tests for 10 different substances, including marijuana, PCP, opiates, cocaine, methamphetamines, amphetamines, tricyclic antidepressants, methadone, barbiturates, and benzodiazepines.
We obtained urine via an ultrasound guided cystocentesis (introducing a needle into the bladder through the abdomen to retrieve the urine). We simply dipped the cartridge into the urine and at 5 minutes the results were read. He tested positive for marijuana (THC).
After obtaining the diagnosis we knew we did not need to continue with additional diagnostic testing. We recommended hospitalization, a small blood test to choose the proper fluids, intravenous fluid therapy, activated charcoal to help bind any marijuana that may have still been in the gastrointestinal tract and monitoring. The client agreed.
IF the patient had just ingested the marijuana and was alert, we would have induced emesis (vomiting). However, given the abnormal behavior for 3-5 hours prior to presentation AND his abnormal neurological exam, inducing emesis was not indicated. Inducing emesis in a dog that was not neurologically normal puts them at risk for aspiration resulting in aspiration pneumonia which can be life threatening.
This patient was given two doses of activated charcoal as the body “recirculates” THC and its metabolites through the gastrointestinal tract and liver thus requiring multiple doses of activated charcoal. The patient was placed on IV fluids due to possible electrolyte abnormalities seen upon giving activated charcoal as well as the patient not being alert enough to take care of himself (eating or drinking) and he was subclinically dehydrated based on blood work We checked his mentation and respiratory rate continuously. We checked his body temperature every 2 hours.
By morning, Bailey was markedly improved and was eating well on his own and was much more alert. He was walking without falling over and was no longer somnolent. He was still a bit more quiet than a normal Yorki but this would resolve over the next day or so. He was discharged about 20 hours after he presented to us and upon a recall was doing great.
Marijuana intoxication can occur secondary to inhalation (“contact high”) but usually occurs due to ingestion. Dogs are much more sensitive to marijuana than people so it does not take much marijuana to be ingested before clinical signs are seen.
Marijuana is a central nervous system depressant that is quickly absorbed after ingestion in any form (medicinal, leaves, flowers, stems, in food, as a resin, etc). It causes euphoria initially, followed by depression. It has potent antiemetic activity. Marijuana intoxication can be lethal so every patient exposed should be examined. However, it does have a wide margin of safety.
Clinical signs can include: ataxia (being wobbly or weak), glazed eyes, dilated pupils, low body temperature (very rarely high temperature), slow OR fast heart rate, somnolence, depression or coma. Depression may be prolonged (usually within 18-72 hours but recovery CAN take up to 5 days depending on the dose ingested), occasionally excitation or hyperesthesia is seen, possibly hypersalivation, possibly tremors, commonly patients will leak urine, and respiratory depression. Although marijuana is a potent antiemetic, vomiting does sometimes surprisingly occur.
The treatment is usually: decontamination (vomiting and/or gastric lavage), activated charcoal administration, monitoring with supportive care on fluids, thermoregulation and frequent monitoring of vitals (temperature, heart rate and respiratory rate). The prognosis is usually very good.
| 
