The home health nurse observes that a female client is using a topical preparation that contains echinacea to treat a canker sore. Her husband expresses concern regarding the effectiveness and safety of using herbs. How should the nurse respond?

Topical echinacea is usually used to soothe burns and can cause damage to the skin.

Echinacea seems to be useful in the treatment of some infections, such as canker sores.

This product is essentially harmless but also is not very beneficial in treating skin infections.

Many of the herbal preparations are helpful primarily because of their placebo effect.