Health food stores and herbal shops are usually friendly places, but it can be daunting to face row after row of unfamiliar things. Here are a few rules to live (and shop) by:

Buy the Right Herb

Sounds obvious, but many plants have similar names, and buying the wrong one is easier than it sounds. For example, “danshen” sounds a lot like “dang shen,” but danshen (Salvia miltiorrhiza) is used to treat cardiovascular disease, while dang shen (Codonopsis pilosula) is an immune tonic and energy booster. To make things worse, some people spell “dang shen” as “dangshen.” Be sure you know both the common and botanical name of the plant you're buying.

Buy the Right Part(s)

Some herbs contain several active compounds that deliver very different actions — and these chemicals are found if different parts of the plant. For example, the gel and juice of the aloe (Aloe vera) plant contain several anti-inflammatory chemicals, which can treat burns (externally) and ulcers (internally). But the latex (the milky sap contained in the rind) contains anthraquinones, which work as a potent stimulant laxative. Thus, unless you're looking for constipation relief, be sure the aloe product you're buying is made from the gel, not the latex.

Buy the Right Preparation

Some herbs are effective medicines when used externally — but dangerous toxins when ingested. Both arnica (Arnica montana) and comfrey (Symphytum officinale), for example, can treat bruises and muscle aches and are used in a variety of creams, ointments, and other topical treatments. But taken internally, each can cause serious problems (arnica is toxic to the heart, comfrey to the liver). Arnica is used internally in homeopathic remedies (see Chapter 1), but they are extremely dilute and so are completely nontoxic.

Herbs are classified as either wild-grown or farm-grown. Wild-grown herbs, as the name implies, grew on their own and were harvested by people in a process called wildcrafting. Farm-grown herbs were produced commercially.

Most people like the idea of using plants that grew naturally, unfettered by humans and all of our issues. But wild-grown herbs may have been exposed to chemicals and pesticides (they may have grown beside a highway or near a polluted stream). In addition, some herbs are endangered in the wild, meaning they stand the best chance of survival if they're cultivated commercially.

The best choice is to buy organically grown herbs that were raised in the United States according to our organic standards. That means they were raised without conventional pesticides, artificial fertilizers, or sewage.