There is certainly something to this last application. In 2000, researchers conducted a small but robustly-designed trial to test claims of nettles' pain-relieving powers. Obviously stinging hurts, but the scientists found that people suffering from arthritic discomfort in their thumb or index finger were more likely to report relief from their aches after nettle stings, compared with a group of people who applied a similar-looking leaf with no sting. (It would be inadvisable to self-administer without medical advice: nettles can cause severe allergic reactions in some people.)
