OBJECTIVE: To examine the patterns of herbal therapy use among adults in the United States and to describe factors associated with herb use.

DESIGN: We examined the use of natural herbs from the 2002 National Health Interview Survey (NHIS). We analyzed factors associated with herb use and reasons for herb use with logistic regression.

RESULTS: Factors associated with herb use include the following: age (45-64 years old), being uninsured, being female, having a higher education, living in the West, using prescription medications or over-the-counter (OTC) medications, and self-identified as "non-Hispanic other." Factors associated with no herb use include being non-Hispanic black and living in the South or Midwest. Seventy-two percent of those who used herbs used prescription medications, and 84% of those who used herbs also used an OTC medication in the prior 12 months. Among adults who used herbs, the most commonly mentioned were echinacea (41%), ginseng (25%), gingko (22%), and garlic (20%). The most frequent conditions for herb use were head or chest cold (30%), musculoskeletal conditions (16%), and stomach or intestinal illness (11%). Among those who used herbs in the prior year, factors associated with using herbs because conventional medical treatments were too expensive included being uninsured, having poor health, and being 25-44 years old.

CONCLUSIONS: Nearly 1 in 5 people in the US population report using an herb for treatment of health conditions and/or health promotion. More than half did not disclose this information to a conventional medical professional.