Page 73 - Pharmaceutics IV (02-06-01305)
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Parenterals: Excipients & additives
Surfactants
Why?
Solubilizing (solutions), wetting (suspensions), or emulsifying agents.
Examples
Different concentration ranges of Cremophor EL, Polysorbate 20 or 80,
PEG 40 castor oil, PEG 60 castor oil, lecithin, or egg yolk
phospholipid. Polysorbate 80 is the most commonly used surfactant
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Parenterals: Excipients & additives
Chelating agents
Why?
They are added to complex and inactivate metals such as copper, iron,
and zinc that generally catalyze oxidative degradation of drug molecules.
They improve the efficacy of antioxidants or preservatives.
Examples
The most widely used chelating agents are edetate disodium
derivatives and salts. Citric and tartaric acids are also used.
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Salma E. EL-Habashy 70
