...made possible by:
central nervous and
bronchodilation, and elevation of blood pressure.
As a drug, Ephedra affects:
The central nervous system
The heart and circulation
The respiratory system
The Central Nervous System
Ephedrine is only one of several drugs (besides norepinephrine, epinephrine,adrenaline, isoprenaline, and amphetamine) which effects the adrenic nervesof the autonomic nervous system that is readily available as a naturalalkaloid. It is obtained from E. equisetina and E. sinica,but it can also be made synthetically. It acts on the sympathetic neuronat its junction with smooth muscle on gland cells.
The Heart and Circulatory System
Many plant derivatives are capable of raising blood pressure due tothe constriction of blood vessels, the stimulation of heartbeat, or both,but only the sympathomimetic amine, ephedrine, from E. sinicaand E. equisetina is widely used. This adrenergic alkaloid hasa pressor effect as a vasopressor drug due largely to an increase in thepatient's cardiac output. Ephedrine stimulates the heart and constrictsresistance-capacitance vessels. It's also widely used in anaesthesia.
The Respiratory System
Because it can be taken orally, it is also prescribed frequently forthe treatment of the common cold, hay fever, and bronchial asthma, forcountering the overdose of depressants, and for relieving especially postauralhypotension. Therapeutic doses of vasopressors like ephedrine may causeheadache, restlessness, anxiety, dizziness, and similar symptoms; convulsionsand arrythmias may result from overdoses. It is also used for the treatmentof sinusitis; treatment includes the administration of analgesics for pain(codeine, morphine), vasoconstrictors (ephedrine) to promote drainage,and specific antibiotics (penicillin, erythromycin) to arrest infection.