A good general-use potency is 30x. Dosages can range from one pill every eight hours to four pills an hour, depending upon need. Suggested dosage rates will be printed on the packaging. Clinical research supports arnica's effectiveness. It is also possible that arnica has preventive benefits.
Many marathoners use it before they race.
Arnica preparations are available in health food stores, certain pharmacies, and mail order homeopathic pharmacies. Arnica should always be used in conjunction with necessary medical treatment. Homeopathic arnica comes in a variety of strengths. I have purchased it in strength 15 and in strength 30. I have not yet started taking it.