SPL UNCLASSIFIED SECTION

For IM, IV or SC Use

Rx only

DESCRIPTION

Ephedrine Sulfate Injection, USP is a sterile solution of 50 mg ephedrine sulfate in Water for Injection.

Ephedrine occurs as fine, white, odorless crystals or powder and darkens on exposure to light. It is freely soluble in water and sparingly soluble in alcohol.

The chemical name of ephedrine sulfate is (C10H15NO)2•H2SO4 benzenemethanol α-[l - (methylamino) ethyl] - sufate (2:1) (salt). Its molecular weight is 428.54. The structural formula is:

CLINICAL PHARMACOLOGY

Ephedrine sulfate is a potent sympathomimetic that stimulates both α and β receptors and has clinical uses related to both actions. Its peripheral actions, which it owes in part to the release of norepinephrine, simulate responses that are obtained when adrenergic nerves are stimulated. These include an increase in blood pressure, stimulation of heart muscle, constriction of arterioles, relaxation of the smooth muscle of the bronchi and gastrointestinal tract, and dilation of the pupils. In the bladder, relaxation of the detrusor muscle is not prominent, but the tone of the trigone and vesicle sphincter is increased.

Ephedrine sulfate also has a potent effect on the CNS. It stimulates the cerebral cortex and subcortical centers, which accounts for its use in narcolepsy.

The cardiovascular responses reported in man include moderate tachycardia, unchanged or augmented stroke volume, enhanced cardiac output, variable alterations in peripheral resistance and usually a rise in blood pressure. The action of ephedrine is more prominent on the heart than on the blood vessels. Ephedrine sulfate increases the flow of coronary, cerebral and muscle blood.

In patients with myasthenia gravis, administration of Ephedrine Sulfate Injection, USP produces a real but modest increase in motor power. The exact mechanism by which ephedrine sulfate affects skeletal muscle contractions is unknown.

INDICATIONS AND USAGE

Ephedrine Sulfate Injection, USP is indicated in the treatment of allergic disorders, such as bronchial asthma The drug has long been used as a pressor agent, particularly during spinal anesthesia when hypotension frequently occurs. In Stokes-Adams syndrome with complete heart block, ephedrine has a value similar to that of epinephrine. It is indicated as a central nervous system stimulant in narcolepsy and depressive states. It is also used in myasthenia gravis.

CONTRAINDICATIONS

Allergic reactions to ephedrine sulfate are rare. The hypersensitivity, if known, is a specific contraindication. Patients hypersensitive to other sympathomimetics may also be hypersensitive to ephedrine sulfate.

PRECAUTIONS

GENERAL - Special care should be used when administering Ephedrine Sulfate Injection, USP to patients with heart disease, angina pectoris, diabetes, hyperthyroidism, prostatic hypertrophy or hypertension and to patients receiving digitalis. Prolonged use may produce a syndrome resembling an anxiety state. Tolerance to ephedrine sulfate may develop, but temporary discontinuance to the drug restores its original effectiveness.

DRUG INTERACTIONS - Concurrent use of ephedrine sulfate with general anesthetics, especially cyclopropane or halogenated hydrocarbons or digitalis glycosides may cause cardiac arrhythmias, since these medications may sensitize the myocardium to the effects of ephedrine sulf