This is the most effective way to use this herb. I've noticed lately that arnica is an ingredient in some commercial sports medicines. Arnica compresses are another way to relieve musculoskeletal pain. Simply mix a tablespoon of arnica tincture in a pint of spring, distilled or filtered water. Dip a gauze pad or sanitary napkin in the mixture, then put it on the arthritic joint or bruised area.
Arnica is poisonous if it gets inside the body.
I usually recommend the 30X dilution as a first aid treatment for trauma. Pour four pills into the cap of the bottle, then toss them into your mouth, under your tongue. The pills can be taken every two hours for the first 24 hours after the injury, and not within a half hour of eating. There are people who may be sensitive to the compound helenalin that's in arnica. If you develop a mild rash, then you probably are one of those helenalin-sensitive people and should stop using arnica immediately.