Therapeutic doses of ephedrine sulfate can inhibit the hypotensive effect of guanethidine, bethanidine, and debrisoquin by displacing the adrenergic blockers from their site of action in the sympathetic neurons. The effect in man is seen as a relative or a complete blockade of the antihypertensive drug by a sudden rise in blood pressure. Concomitant use of Ephedrine Sulfate Injection, USP and oxytocics may cause severe hypotension.

Monoamine oxidase inhibitors may potentiate the pressor effect of ephedrine sulfate, possibly resulting in a hypertensive crisis. Ephedrine Sulfate Injection, USP should not be administered during or within 14 days following the administration of MAO inhibitors.

PREGNANCY CATEGORY C - Animal reproduction studies have not been conducted with Ephedrine Sulfate Injection. USP Also, it is not known whether the drug can cause fetal harm when administered to a pregnant woman or can affect reproduction capacity. Ephedrine Sulfate Injection, USP should be given to a pregnant woman only if clearly indicated.

It is not known what effect Ephedrine Sulfate Injection, USP may have on the newborn or on the child's later growth and development when the drug is administered to the mother just before or during labor.

NURSING MOTHERS - Ephedrine sulfate is excreted in breast milk. Use by nursing mothers is not recommended because of the higher than usual risks for infants.

ADVERSE REACTIONS

With large doses of ephedrine sulfate most patients will experience nervousness, insomnia, vertigo, headache, tachycardia, palpitation and sweating. Some patients have nausea, vomiting and anorexia. Vesical sphincter spasm may occur and result in difficult and painful urination. Urinary retention may develop in males with prostatism.

Precordial pain and cardiac arrhythmias may occur following administration of Ephedrine Sulfate Injection, USP

DRUG ABUSE AND DEPENDENCE

Prolonged abuse of Ephedrine Sulfate Injection, USP can lead to symptoms of paranoid schizophrenia. When this occurs, patients exhibit such physical signs as tachycardia, poor nutrition and hygiene, fever, cold sweat and dilated pupils.

Some measure of tolerance may develop with prolonged or excessive use but addiction does not occur. Temporary cessation of medication and subsequent readministration restores its effectiveness.

OVERDOSAGE

SYMPTOMS - The principal manifestation of ephedrine sulfate poisoning is convulsions. In acute poisoning the following signs and symptoms may occur: nausea, vomiting, chills, cyanosis, irritability, nervousness, fever, suicidal behavior, tachycardia, dilated pupils, blurred vision, opisthotonos, spasms, convulsions, pulmonary edema, gasping respirations, coma and respiratory failure. Initially, the patient may have hypertension, followed later by hypotension accompanied by anuria.

TREATMENT - If respirations are shallow or cyanosis is present, artificial respiration should be administered. Vasopressors are contraindicated. In cardiovascular collapse blood pressure should be maintained.

ANTIDOTE - For hypertension, 5 mg phentolamine mesylate diluted in saline may be administered slowly intravenously, or 100 mg may be given orally. Convulsions may be controlled by diazepam or paraldehyde. Cool applications and dexamethasone 1 mg/kg, administered slowly intravenously, may control pyrexia.
 
DOSAGE AND ADMINISTRATION

ADULTS - Th