sustained bronchial relaxation is responsible for the greatest use of ephedrine--to
facilitate breathing in chronic asthmatic conditions, and in treatment of hay fever and
colds. Ephedrine (or compounds very similar to it in action) is commonly used in many
preparations for the treatment of colds. Also, this drug may be given by intramuscular
or intravenous injection prior to the administration of spinal anesthesia, because this
use of the drug will enable blood pressure to be maintained during the operation.
Ephedrine has a stimulating effect upon the central nervous system that is greater than
that obtained with epinephrine. Ephedrine also acts to relieve nasal congestion.
b. Administration. The usual dose to be given either orally or parenterally is
25 to 50 mg. Two or three drops of a one- percent solution are usually given as nose
drops.
c. Differences Between Epinephrine and Ephedrine. Although ephedrine
and epinephrine are quite similar in action, there are a number of differences that are
important clinically.
(1) Ephedrine is effective when given orally, whereas epinephrine must be
given by injection (except when used as a spray or inhalation for asthmatic attacks.)
(2) Ephedrine has a longer duration of action than epinephrine does, but
ephedrine also has a slower onset of action. These properties make ephedrine better
suited for the treatment of chronic asthma and of colds.
(3)
Epinephrine has a greater vasoconstricting effect than ephedrine.
(4)
A tolerance to ephedrine may be acquired but not to epinephrine.
(5) Ephedrine has a greater stimulating effect upon the central nervous
system than does epinephrine.
(6)
Ephedrine has a much lower potency than epinephrine.
d. Untoward Effects. The main toxic effect of ephedrine is anxiety. A
tolerance to the drug may be acquired.
e. Cautions and Contraindications. Clients may acquire a tolerance to the
drug. If ephedrine is to be used in nose drops, the drug should be dissolved in water
and not in oil. Continuous use of an oily preparation in the nose can cause lipid
pneumonia (pneumonia due to the aspiration of oil). Liquid preparations of ephedrine
should be protected from freezing. Like epinephrine, ephedrine should be used with
caution, if at all, in clients with heart disease, high blood pressure, hyperthyroidism,
and diabetes mellitus.
f. How Supplied. Ephedrine sulfate is supplied as a powder, as a 25-mg
capsule, and as an injection which contains 25 or 50-mg of the drug per ml.
MD0913
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