Resembling a black-eyed Susan, Echinacea or purple coneflower is a North American perennial that is indigenous to the central plains where it grows on road banks, prairies, fields and in dry, open woods. It is also called snake root because it grows from a thick black root that Indians used to treat snake bites.

Herbalists consider Echinacea one of the best blood purifiers and an effective antibiotic. It activates the body's immune system increasing the chances of fighting off any disease. This popular herb has been used to help ward off the common cold and to relieve the symptoms of hay fever.

The constituents of Echinacea include essential oil, polysaccharides, polyacetylenes, betain, glycoside, sesquiterpenes and caryophylene. It also contains copper, iron, tannins, protein, fatty acids and vitamins A, C, and E. The most important immune-stimulating components are the large polysaccharides, such as inulin, that increase the production of T-cells and increase other natural killer cell activity. Fat-soluble alkylamides and a caffeic acid glycoside called echinacoside also contribute to the herb's immune empowering effects.

It has been shown in animal and human studies to improve the migration of white blood cells to attack foreign microorganisms and toxins in the bloodstream. Research suggests that Echinacea's activity in the blood may have value in the defense of tumor cells.

Derived from the plant Ephedra, Ephedra is a shrub-like plant that is found in desert regions in central Asia and other parts of the world. The dried greens of the plant are used medicinally. Ephedra is a stimulant containing the herbal form of ephedrine, an FDA-regulated drug found in over-the-counter asthma medications.

Ephedra's main active medical ingredients are the alkaloids ephedrine and pseudoephedrine. The ephedras also contain various tannins and related chemicals. The stem contains 1-3% total alkaloids, with ephedrine accounting for 30-90% of this total. The concentrations of these alkaloids depend upon the particular species of Ephedra used. Ephedrine alkaloids are amphetamine-like compounds used in OTC and prescription drugs with potentially lethal stimulant effects on the central nervous system and heart.

The FDA has received more than 800 reports of adverse effects associated with use of products containing ephedrine alkaloid since 1994. These serious adverse effects, include hypertension (elevated blood pressure), palpitations (rapid heart rate), neurophathy (nerve damage), myopathy (muscle injury), psychosis, stroke, memory loss, heart rate irregularities, insomnia, nervousness, tremors, seizures, heart attacks, and death. The agency has proposed to prohibit the marketing of dietary supplements containing 8 milligrams or more of ephedrine alkaloids per serving.