The herb may be taken as a tea or an infusion, or it may be combined into powdered drink mixes or capsules. The active components of Ephedra sinica are alkaloids, including ephedrine and pseudoephedrine. Pharmacologically, ephedrine and pseudoephedrine are sympathomimetic alkaloids. This stimulation results in peripheral vasoconstriction and cardiac stimulation, causing increased blood pressure, tachycardia, mydriasis, ataxia, and restlessness. Central nervous system effects such as tremors and seizures may be seen.
People often report vertigo, insomnia, and headache.
The pseudoephedrine component causes more bronchodilation and decreases nasal congestion better than the ephedrine alkaloid. 3,4 Ephedrine and pseudoephedrine are metabolized in the liver and excreted in the urine. Toxic effects are generally limited to the cardiovascular and central nervous systems. Doses are frequently difficult to calculate for herbal products because of seasonal growing conditions and natural variances of the alkaloids within the plant. Clinical signs usually develop within 30 minutes to several hours after ingestion.