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87 MAY/JUNE 2017 ■ TVPJOURNAL.COM PRACTICAL TOXICOLOGY used to address tremorgenic mycotoxin toxicity. Because of the rapid absorption of penitrem A and rapid onset of clinical neurologic signs, the window of opportunity to safely induce emesis and administer activated charcoal is generally limited. 4,9 As the ability to safely induce emesis and/ or give activated charcoal may be limited, gastric lavage may provide some benefit. Patients presenting with severe signs (eg, notable hyperthermia, severe muscle tremors, seizures) may require heavy sedation or even anesthesia to control clinical signs. Once clinical signs are appropriately controlled, patient size and time of toxin exposure become important factors in deciding whether gastric lavage should be performed. Radiographs may be useful to assess how much material is in the stomach. The size of the patient dictates the bore of orogastric tube that can be used; recovering food material through a small-bore tube may prove futile. 5 Instilling activated charcoal after gastric lavage via stomach tube may be considered but should be weighed against risk for aspiration. 9 Symptomatic Care Control of tremors is paramount ( Box 2 ); however, this may be a challenge. While diazepam and barbiturates are advised, they may not always be effective (eg, diazepam). Heavy sedation also places the pet at risk for aspiration. Methocarbamol has been used with success. Other drugs used to control tremors include propofol and gas anesthesia. IV fluids should be administered to all patients that do not have physical contraindications to fluid therapy. Benefits of IV fluids include correction of electrolyte abnormalities and fluid loss secondary to vomiting or diarrhea, cooling (in patients with hyperthermia), and minimizing the risk of kidney injury from myoglobinuria secondary to rhabdomyolysis. Antiemetics should be used in vomiting patients to limit risk of aspiration, dehydration, and electrolyte abnormalities. The patient's temperature should be monitored closely for hyperthermia. Management of muscle tremors will help address the cause of hyperthermia, but other cooling measures may be warranted, such as wetting the patient, fans, and IV fluids; in severe cases, cold packs or running the IV fluid line through cool water may be warranted. Cooling measures should be discontinued when the temperature reaches 102.5°F to prevent rebound hypothermia. 12 Intravenous Lipid Emulsion Therapy Intravenous lipid emulsion (ILE) therapy is a newer therapy that is gaining popularity in veterinary medicine. Although initially designed to treat local anesthetic overdoses in humans, its use has been expanded to include a variety of lipophilic drug overdoses in both humans and veterinary species. The mechanism of action of ILE therapy is not known; however, it likely includes a "lipid sink" or "lipid shuttle," where lipid-soluble drugs are transiently sequestered in intravenous liposomes, as well as direct cardiovascular effects. 13 BOX 2. Drugs Used to Control Tremors • Methocarbamol*: 55−220 mg/kg IV; administer half the estimated dose ≤2 mL/min, wait until the patient starts to relax, and then continue to administer to effect 10 • Diazepam: 0.5−1 mg/kg IV; 0.1-2 mg/kg/h CRI 10 • Midazolam: 0.07−2 mg/kg IV or IM; 0.05−0.5 mg/kg/h CRI 10 • Phenobarbital: 2−20 mg/kg IV: administer 2−5 mg/kg IV bolus q20min to effect 11 • Propofol: 6 mg/kg IV followed by 0.1−0.6 mg/kg/min CRI 10 *Extra-label dosing for methocarbamol: Consider initial IV bolus followed by constant-rate infusion (CRI) or multiple IV boluses, titrating dose and frequency to effects. The labeled maximum dosing of 330 mg/kg/d can be exceeded, if necessary, but monitoring for central nervous system depression, seizures, and hypotension is warranted. 10