obtain and maintain the desired effect. Blood pressure readings must be taken at 5 to
15 minute intervals to avoid overdosage. Someone must stay with the client
continuously to see that the drug does not leak into the subcutaneous tissue, because
dangerous necrosis of tissue can result from such leakage.) However, the first
definitive treatment of shock, after obvious bleeding has been controlled, is the
restoration of adequate blood volume. When levarterenol is used to treat shock,
despite adequate restoration of blood pressure, failures occur in approximately 50
percent of cases. The rationale of its use is questionable.
b. Isoproterenol Hydrochloride (Isuprel Hydrochloride). Isoproterenol is very
closely related chemically to epinephrine, but it is a pure vasodilator. It is used in the
symptomatic relief of asthma. Unreliable when administered orally, it is usually given
c. Oxymetazoline Hydrochloride (Afrin Hydrochloride). Oxymetazoline
hydrochloride is included as a 0.05 percent solution in the Battalion Aid Station Medical
Equipment Set. It is used as a decongestant for allergic rhinitis (inflammation of the
mucous membranes of the nose).
d. Phenylpropanolamine Hydrochloride (Propradrine). This drug has actions
similar to ephedrine, but with slightly longer action and less CNS stimulation. It is used
in nasal congestion and bronchial asthma.
e. Propylhexedrine (Benzedrex). This is a decongestant used by inhalation.
f. Xylometazoline Hydrochloride (Otrivin Hydrochloride). This is a nasal
Section IV. VASODILATOR DRUGS
The nitrites and organic nitrates are a group of drugs whose basic action is to
relax smooth muscles. They produce vasodilation, which results in a lowering of blood
pressure, venous dilatation and pooling, and a decreased cardiac workload. Their
chief use is in the relief of attacks of angina pectoris (spasmodic suffocative chest
pain), and they may be used to relieve acute attacks of hypertension and asthma.
These drugs have a relatively short duration of action, however, and are not suited for
the treatment of chronic hypertension. Because better drugs are available, they are not
routinely used in the treatment of asthma. Untoward effects of these drugs include
flushing of the skin, headache, nausea, vomiting, dizziness, fainting, and a faster
heartbeat. A tolerance to these drugs is easily acquired; therefore, a client may need
to increase the dosage progressively to obtain the desired response from the drug.