External antirheumatic and antineuralgic herbal remedies in the traditional medicine of north-eastern Italy.

The utilization of more than 90 plant species as folk external remedies to treat rheumatic and arthritic diseases is reported, and their possible effectiveness is discussed according to present phytochemical and pharmacological knowledge. Some of the plant species used exhibit skin-irritant properties (protoanemonin, isothiocyanate or allicine yielding plants and species containing capsaicin, oleoresins, volatile oils, resinous principles, alkaloids). The effectiveness of other herbal remedies depends on their content of salicyl derivatives. A considerable number of the plant species utilized contain chemical products (triterpenoid or steroid compounds, alkaloids) for which anti-inflammatory properties have been demonstrated.