Ephedrine

Ephedrinum

Mechanism :

Ephedrine is a sympathomimetic amine. Therapeutic doses of ephedrine produce relaxation of smooth muscle and, when norepinephrine stores are intact, cardiac stimulation and increased blood pressure. Ephedrine stimulates both alpha and beta receptors and its peripheral actions are due partly to norepinephrine release and partly to direct effect on receptors. Ephedrine may deplete norepinephrine stores in sympathetic nerve endings. Central nervous system effects are similar to those of amphetamine drugs but less pronounced. The central effects of ephedrine are overshadowed to a large extent by its peripheral effects.

Indication :

• Acute bronchospasm
• Anesthesia related hypotension
• Nasal congestion

Contraindications :

Ephedrine is contraindicated in patients with known hypersensitivity to sympathomimetic amines and in patients with angle closure glaucoma. It should not be used in patients anesthetized with agents such as cyclopropane or halothane as these agents may sensitize the heart to the arrhythmic action of sympathomimetic drugs. Ephedrine should not ordinarily be used in those cases where vasopressor drugs may be contraindicated, as in thyrotoxicosis, diabetes, in obstetrics when maternal blood pressure is in excess of 130/80 and in hypertension and other cardiovascular disorders. Caution in children <3 months.

Dosing :

Adverse Effect :

Hypertension sufficient to produce cerebral hemorrhage, headache, dizziness, restlessness, pallor, anxiety, palpitation, tension, confusion, tremor, weakness, delirium hallucinations, respiratory difficulty, sweating, nausea or vomiting.

Interaction :

Sympathomimetic drugs: Possible additive effects and increased toxicity.
Alpha-Adrenergic Blocking Agents: May reduce the vasopressor response to ephedrine by causing vasodilation.

Hepatic Dose :