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Intravenous lipid emulsion (IVLE) (e.g. Intralipid) infusion has been increasingly used as antidotal treatment of toxicosis from various lipophilic agents (Fernandez et al., 2011; Gwaltney-Brant and Meadows, 2012; Kaplan and Whelan, 2012). IVLE is composed of neutral, medium to long-chain triglycerides derived from plant oils (e.g. soybean, safflower), egg phosphatides and glycerine, formulated primarily as a source of essential fatty acids for patients requiring parenteral nutrition (Gwaltney-Brant and Meadows, 2012). The exact mechanism of antidotal action of IVLE is unknown. The sequestration effect theory proposes that IVLE acts as pharmacological ‘sink’ for lipid soluble compounds decreasing their tissue availability and increasing their clearance (Kaplan and Whelan, 2012). IVLE expands the plasma lipid phase creating a discrete compartment that sequesters lipophilic agents and prevents them from reaching their sites of action. In addition, the expanded plasma lipid phase creates a concentration gradient that facilitates the passage of the lipophilic compounds from the interstitial space into the intravascular space. Potential adverse effects of IVLE infusions include: interference with lipophilic medications (i.e. methocarbamol, diazepam, phenobarbitone, propofol) administered for symptomatic or supportive care; pancreatitis due to persistent lipaemia; and hypersensitivity due to IVLE components (Gwaltney-Brant and Meadows, 2012). Based on growing number of case reports in veterinary medicine, IVLE infusion shows promise in the management of toxicosis from a variety of lipophilic agents, including macrocyclic lactones and pyrethrin compounds (Pritchard, 2010; Clarke et al., 2011; Haworth and Smart, 2012; Epstein and Hollingsworth, 2013). More studies are needed to determine optimum time of initiation, dosing regimens and margin of safety of IVLE as antidotal treatment for different lipid soluble toxicities. Treatment protocols are likely to be affected by the degree of lipid solubility and half-life of the toxin. The protocol recommended in Table 4.1 is based on the human literature and veterinary case reports. Care must be taken to use aseptic technique when handling and administering any lipid emulsions as they can promote bacterial growth (Kaplan and Whelan, 2012).