Glycerin

Synonyms: Croderol; E422; glicerol; glycerine; glycerolum; Glycon G-100; Kemstrene; Optim; Pricerine; 1,2,3-propanetriol; trihydroxypropane glycerol

Description: Glycerin is a clear, colorless, odorless, viscous, hygroscopic liquid; it has a sweet taste, approximately 0.6 times as sweet as sucrose

Chemical Name: Propane-1,2,3-triol

Antimicrobial preservative; cosolvent; emollient; humectant; plasticizer; solvent; sweetening agent; tonicity agent.

• Glycerin is used in a wide variety of pharmaceutical formulations including oral, otic, ophthalmic, topical, and parenteral preparations.

• In topical pharmaceutical formulations and cosmetics, glycerin is used primarily for its humectant and emollient properties.

• Glycerin is used as a solvent or cosolvent in creams and emulsions.

• Glycerin is additionally used in aqueous and nonaqueous gels and also as an additive in patch applications.

• In parenteral formulations, glycerin is used mainly as a solvent and cosolvent.

• In oral solutions, glycerin is used as a solvent, sweetening agent, antimicrobial preservative, and viscosity-increasing agent. It is also used as a plasticizer and in film coatings.

• Glycerin is used as a plasticizer of gelatin in the production of soft-gelatin capsules and gelatin suppositories.

Glycerin may explode if mixed with strong oxidizing agents such as chromium trioxide, potassium chlorate, or potassium permanganate. In dilute solution, the reaction proceeds at a slower rate with several oxidation products being formed. Black discoloration of glycerin occurs in the presence of light, or on contact with zinc oxide or basic bismuth nitrate. An iron contaminant in glycerin is responsible for the darkening in color of mixtures containing phenols, salicylates, and tannin. Glycerin forms a boric acid complex, glyceroboric acid, that is a stronger acid than boric acid.

Glycerin occurs naturally in animal and vegetable fats and oils that are consumed as part of a normal diet. Glycerin is readily absorbed from the intestine and is either metabolized to carbon dioxide and glycogen or used in the synthesis of body fats. Glycerin is used in a wide variety of pharmaceutical formulations including oral, ophthalmic, parenteral, and topical preparations. Adverse effects are mainly due to the dehydrating properties of glycerin

Observe normal precautions appropriate to the circumstances and quantity of material handled. Eye protection and gloves are recommended. Glycerin is combustible and may react explosively with strong oxidizing agents

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