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Calcium Hydroxide

    Synonyms: Calcium hydrate; calcii hydroxidum; E526; hydrated lime; slaked lime.

    Description:  Calcium hydroxide occurs as a white or almost white, crystalline or granular powder. It has a bitter, alkaline taste. Calcium hydroxide readily absorbs carbon dioxide to form calcium carbonate.

    Chemical Name: Calcium hydroxide

    Alkalizing agent; astringent; therapeutic agent.

    • Calcium hydroxide is a strong alkali and is used as a pharmaceutical pH adjuster/buffer and antacid in topical medicinal ointments, creams, lotions, and suspensions, often as an aqueous solution (lime water).

    • It forms calcium soaps of fatty acids, which produce water-in-oil emulsions (calamine liniment), and it is also used as a topical astringent.

    • Calcium hydroxide is a common cosmetic ingredient in hairstraightening and hair-removal products, and in shaving preparations.

    • In dentistry, it is used as a filling agent and in dental pastes to encourage deposition of secondary dentine.

    • Calcium hydroxide was traditionally used as an escharotic in Vienna Paste.

    Incompatible with strong acids, maleic anhydride, phosphorus, nitroethane, nitromethane, nitroparaffins, and nitropropane. Calcium hydroxide can be corrosive to some metals.

    Calcium hydroxide is used in oral and topical pharmaceutical formulations. It is mildly toxic by ingestion. In the pure state, calcium hydroxide is a severe skin, eye, and respiratory irritant, and it is corrosive, causing burns.

    Observe normal precautions appropriate to the circumstances and quantity of the material handled. Avoid contact with eyes, skin, and clothing. Avoid breathing the dust. Gloves, eye protection, respirator, and other protective clothing should be worn

    Potassium hydroxide; sodium hydroxide.