Functional Category
Oleaginous vehicle; solvent.
Applications in Pharmaceutical Formulation
Peanut oil is used as an excipient in pharmaceutical formulations primarily as a solvent for sustained-release intramuscular injections. It is also used as a vehicle for topical preparations and as a solvent for vitamins and hormones. In addition, it has been part of sustained-release bead formulations,(2) nasal drug delivery systems,(3) and controlled-release injectables.(4) Therapeutically, emulsions containing peanut oil have been used in nutrition regimens, in enemas as a fecal softener, and in otic drops to soften ear wax. It is also administered orally, usually with sorbitol, as a gall bladder evacuant prior to cholecystography. Peanut oil is also widely used as an edible oil.
Description
Peanut oil is a colorless or pale yellow-colored liquid that has a faint nutty odor and a bland, nutty taste. At about 38C it becomes cloudy, and at lower temperatures it partially solidifies.
Stability and Storage Conditions
Peanut oil is an essentially stable material.(6) However on exposure to air it can slowly thicken and may become rancid. Solidified peanut oil should be completely melted and mixed before use. Peanut oil may be sterilized by aseptic filtration or by dry heat, for example, by maintaining it at 1508C for 1 hour.(7) Peanut oil should be stored in a well-filled, airtight, lightresistant container, at a temperature not exceeding 408C. Material intended for use in parenteral dosage forms should be stored in a glass container.
Incompatibilities
Peanut oil may be saponified by alkali hydroxides.
Safety
Peanut oil is mildly laxative at a dosage of 15–60 mL orally or of 100–500 mL rectally as an enema. Adverse reactions to peanut oil in foods and pharmaceutical formulations have been reported extensively.(8–18) These include severe allergic skin rashes(8,9) and anaphylactic shock following consumption of peanut butter.(10) Some workers have suggested that the use in infancy of preparations containing peanut oil, including infant formula and topical preparations, is associated with sensitization to peanut, with a subsequent risk of hypersensitivity reactions, and that such products should therefore be avoided or banned.(8–12) However, the role of pharmaceutical preparations in later development of hypersensitivity is disputed since such preparations contain highly refined peanut oil that should not contain the proteins associated with allergic reactions in susceptible individuals.(13–15) Peanut oil is harmful if administered intravenously and it should not be used in such formulations.(16