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Parenteral preparations are sterile, pyrogen-free liquids (solutions, emulsions, or suspensions) or solid dosage forms containing one or more active ingredients, packaged in either single-dose or multidose containers. They are intended for administration by injection, infusion, or implantation into the body.
There are four main forms of parenteral preparations: injections, intravenous infusions (large volume parenterals), powders for injections, and implants. Certain injections and intravenous infusions may be presented in the form of sterile concentrated solutions, which must be suitably diluted before use.