What folk medicine says American herbalists have used all three botanicals since the 19th century: They applied ash leaves to relieve arthritis, and poplar and goldenrod extracts to ease joint pain.  What we know Studies show that poplar contains salicin, the active ingredient in aspirin. Ash and goldenrod have anti-inflammatory properties. A review looked at four studies in which 820 patients took either Phytodolor or a prescription nonsteroidal anti-inflammatory drug (NSAID) similar to Vioxx for 2 to 4 weeks. The herb blend and the drug reduced joint pain by the same amount. Side effects—such as stomach pain and dizziness—were also similar, but incidence was much lower among the herb group.  What research shows Researchers from the University of Heidelberg in Germany treated human cells with either Phytodolor or aspirin. They found that the herbs were twice as effective as aspirin at inhibiting the inflammatory response and suppressing the COX-2 enzyme. Blocking this enzyme impedes the production of chemical messengers called prostaglandins, which trigger swelling and pain.  What to take Phytodolor is mainly sold in Europe; a version of it, Aspen Arthro-Blend, is available from Vital Botanicals. (Don’t use Phytodolor if you’re pregnant or allergic to aspirin.) Dose: Take 20 to 40 drops mixed into water every 4 hours. Cost: $19 at Vital Botanicals.