Section III. CLASSES OF PREPARATIONS CONTAINING ALCOHOL
a. Definition. Spirits are solutions of volatile substances in alcohol or alcohol
and water. A solvent consisting of alcohol and water is said to be hydroalcoholic. The
percentage concentration of volatile substances in a spirit may range from 5 to 20
percent. The active ingredient of a spirit may be solid, liquid, or gaseous.
b. Uses. Spirits are generally used internally for their medicinal value, by
inhalation for their medicinal value, and as flavoring agents. Spirits are sometimes used
in the preparation of aromatic waters and other medicinals that require flavoring.
c. Incompatibilities. Spirits, because of their high alcoholic content and volatile
oil content, do not mix well with water or dilute alcoholic solutions. Such a dilution
usually results in separation of the oil. In general, spirits should not be mixed with salt
solutions because salts are often soluble in water but insoluble in alcohol and may
precipitate in a hydro-alcoholic solution. Spirits should be kept in tight containers
because they evaporate easily. They should also be protected from light by dark,
amber colored bottles.
a. Definition. Tinctures are alcoholic or hydro-alcoholic solutions prepared from
vegetable drugs or chemical sources. Thus, most contain extracts from plants. Unlike
spirits, they are usually made from nonvolatile substances.
(1) Potent tinctures. Tinctures of potent drugs, called potent tinctures,
usually are limited to only 10-gm of original substance for every 100-ml of final solution.
(2) Non-potent tinctures. Most other tinctures, the non-potent tinctures, are
limited to 20-gm of original substance for every 100-ml of final solution.
(3) Fresh drug tinctures. Lemon Tincture, USP and Sweet Orange Peel
Tincture, USP, fresh drug tinctures, utilize 50-gm of original substance, the outer rind of
the fruit, for every 100-ml of final solution.
b. Uses. With the increasing use of pure drug compounds, including synthetics
as well as plant drugs, there is less need for plant extracts such as tinctures. However,
a number of tinctures are used to prepare other pharmaceutical products, either for their
flavoring or for the medicinal value. Other tinctures are used as local anti-infectives.