Echinacea, Safe to Give to Child?

What can you tell me about echinacea? Can I give it to a child? If so, how much?

Echinacea is one of the best immune-stimulating herbs known. Echinacea extracts are now widely consumed for this purpose. Because the effect is strongest when echinacea enters the bloodstream directly, it is important to take it in a form that can be readily absorbed without degradation. In the digestive tract the active constituents are thought to be broken down before they get a chance to pass through the walls of the stomach and bowels. For this reason taking echinacea in a liquid form is recommended instead of pills or capsules. In a liquid form the active constituents are absorbed through the membranes of mouth. Pills and capsules are not likely to be effective.
According Steven Foster, author of "Echinacea, Nature's Immune Enhancer," there are few risks associated with use of echinacea and he mentions none for children specifically. The main risk is inappropriate stimulation of the immune system in people suffering from auto-immune diseases such as multiple sclerosis and lupus. Allergic reactions occur in rare cases. This applies to adults and children.
Commercial echinacea products tested on rats and mice were shown to be non-toxic at doses far in excess of those normally used for human consumption. The typical dose is the number of drops corresponding to 900 milligrams of dried powder. If the drops you are taking are made as a 1 part echinacea to 5 parts solvent (1:5 tincture), then the typical daily dose translates to 90 drops daily.