Intralipid is a brand name for the first safe fat emulsion for human use, approved in 1962 in Europe and invented by Professor Arvid Wretlind, Sweden. The FDA initially would not approve the product due to prior experience with another fat emulsion. It was approved in the United States in 1972. It is used as a component of parenteral nutrition for patients who are unable to get nutrition via an oral diet. It is an emulsion of soy bean oil, egg phospholipids and glycerin. It is available in a 10%, 20% and 30% concentration. The 30% concentration is not approved for direct intravenous infusion, but should be mixed with amino acids and dextrose as part of a total nutrient admixture.
Intralipid provides essential fatty acids, linoleic acid (LA), an omega-6 fatty acid, alpha-linolenic acid (ALA), an omega-3 fatty acid.
Some preparations of the anaesthetic drugs propofol and etomidate (the vehicle for etomidate is propylene glycol) are supplied using Intralipid as a vehicle.
Weinberg et al. have published data indicating Intralipid is effective in treating experimental models of severe cardiotoxicity secondary to intravenous overdose of local anaesthetic drugs such as bupivacaine. Recent case reports have been published of the successful use of lipid emulsion in this way to save patients who were unresponsive to the usual resuscitation methods. All patients recovered completely shortly after intravenous injections of lipid.
Intralipid is also widely used in optical experiments to simulate the scattering properties of biological tissues. Solutions of appropriate concentrations of intralipid can be prepared that closely mimic the response of human or animal tissue to light at wavelengths in the red and infrared ranges where tissue is highly scattering but has a rather low absorption coefficient.