Syrups: contains ↑ sugar concentration. Sweet and viscous. Syrup NF (simple syrup): 85% w/v sugar. Sugars have low...
Syrups: contains ↑ sugar concentration.
Sweet and viscous.
Syrup NF (simple syrup): 85% w/v sugar. Sugars have low solvent capacity for water
soluble drugs because hydrogen bonding between sugar and water is very
strong. Dilute sucrose solutions are
excellent media for microbial growth. As
sugar concentration approaches saturation, the solution becomes self-preserved,
however temperature fluctuations may cause sugar crystallization. Syrup USP
is self-preserved with ↓ crystallization potential.
Elixirs: contain alcohol as a solvent (5-40%).
Elixirs become turbid when diluted by aqueous liquids. Alcohol ↑ salt taste. Salts also have limited solubility in
alcohol.
Aromatic elixir NF: mixture of two alcohol concentrations resulting in 22% alcohol.
Aromatic waters: are
saturated aqueous solutions of volatile oils.
Used for flavoring. Stored in
tight, light resistant containers.
Adding large amount of water soluble drug may cause insoluble layer to
form (salting out) due to better attraction with the water solvent than the
oils.
Spirits (essences): volatile substances in 50-90% alcohol. It water is added, oils separate. Used medicinally or as flavors. Store in tight containers.
Tinctures:
stable alcohol
solutions of chemicals or soluble constituents or vegetable drugs. Prepared using extraction using maceration or
percolation. Alcohol content varies
widely.
Fluidextracts: liquid extracts of vegetable drugs that contain alcohol as a solvent,
preservative, or both. Prepared by
percolation. Ten times as concentrated
and potent as tinctures (100% vs. 10%).
Mouthwashes: use alcohol or glycerin to dissolve volatile
ingredients.
Astringents: locally applied solutions that ppt
protein. Astringents ↓ cell permeability
without causing injury. They cause
constriction, wrinkling and blanching of skin.
They ↓ secretions and are used as antiperspirants. Examples: alulminum acetate, aluminum
subacetate, calcium hydroxide.
Antibacterial topical solutions: e.g. benzalkonium chloride, strong iodine,
providone-iodine. .
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