Medicinal plants: historical and cross-cultural usage patterns.

An attempt is made to review the prevalence of medicinal herb use in different societies and the various lines of evidence for its effectiveness for particular health needs and the alleviation of disease conditions. Published scientifically collected data and anecdotal reports representing numerous populations are compiled and evaluated. Original research findings from Caribbean, American, and Caribbean-American samples are included in the comparisons. Medicinal plant products have been successfully administered both externally and internally in several different forms for a wide range of health problems cross-culturally since prehistoric times. Certain toxic effects and contraindications have also been recorded. Many botanical medications contain curative bioactive chemical ingredients which have proven to be valuable as primary or supplemental therapies when carefully applied. Further research will ultimately clarify their appropriate roles in the treatment of diseases and injuries as well as in preventive health maintenance.