4-9.
METARAMINOL BITARTRATE INJECTION
a. Action and Uses. Metaraminol (Aramine) is a vasopressor drug used to
raise the blood pressure of clients in some types of hypotensive states. Metaraminol
has a longer duration of action than epinephrine: The vasopressor effect of an
intramuscular dose of 5 mg of metaraminol lasts for about 1 1/2 hours.
b. Administration. This drug can be given by either intramuscular or
intravenous injection. It should not be given subcutaneously, as tissue sloughing may
result when it is so administered. The usual dose is 1 ml of a one percent preparation,
which is 10 mg of the drug. The drug may be included in solution for intravenous
infusion, the rate of flow being regulated according to the client's response to the drug.
c. Untoward Effects. Toxic reactions to a therapeutic dose of the drug are
rare, but hypertension may result, if too much is given. Hypertension is especially
dangerous in a client with an open wound, since the elevated blood pressure may lead
to fresh hemorrhage.
d. Cautions and Contraindications. This drug should not be given by
subcutaneous injection, since tissue sloughing may result from such administration.
Metaraminol deteriorates after 60 months; therefore, the date on the package should be
checked before the drug is given. When this drug is given in a solution by the
intravenous route, the client's blood pressure should be monitored frequently (5 to 10
minute intervals) and the rate of flow adjusted to the client's response.
e. How Supplied. Metaraminol bitartrate injection is supplied in 10-ml vials,
each milliliter containing 10-mg of metaraminol.
4-10. PHENYLEPHRINE HYDROCHLORIDE
Phenylephrine (Neo-Synephrine) is similar in structure and action to epinephrine
and has a vasopressor action when injected or taken orally. When applied locally to
mucous membrane, it acts as a vasoconstrictor, reducing swelling and congestion, and
is the most widely used nose drop preparation for decongestion. It is often combined
with local anesthetics in a similar manner to epinephrine. Phenylephrine is also used
in eye solutions as a conjunctival decongestant, vasoconstrictor, and mydriatic. Its
action is superior to that of ephedrine in maintaining blood pressure during spinal
anesthesia.
4-11. MISCELLANEOUS SYMPATHOMIMETICS
a. Levarterenol Bitartrate Injection (norepinephrine; Levophed). Levarterenol
is provided in the Field Shock Treatment Surgical Instrument and Supply Set as a 0.2
injection in 4-ml ampules. It produces general vasoconstriction without stimulating the
heart. (In the treatment of shock, one ampule may be added to 1000 ml of a dextrose
solution and given by intravenous infusion. Rate of flow must be carefully regulated to
MD0913
4-9