Purchase topical arnica gel made by popular brands, such as Arnicare, in pharmacies throughout the United States, or purchase gels online on websites such as the Vitamin Shoppe. The gel does not require a prescription, as stated by MedicineNet.
The herb arnica montana is used to relieve stiffness, bruising, swelling, muscle aches and pain. Gels offer an arnica concentration of 7 or 8 percent, notes MedicineNet. Although early studies of arnica gels and ointments for the treatment of arthritic pain and swelling of the hand and knee have shown positive results, ongoing research as to the homeopathic medicine's effectiveness is still mixed, according to WebMD. To use the product, adults and children over the age of 2 should apply a thin layer of gel to the affected area or injury three to four times per day or until symptoms subside, as instructed by MedicineNet. Avoid placing gel in open wounds or near the eye.
The herb itself is toxic when eaten and has been classified as unsafe by the FDA, but homeopathic doses of arnica are considered safe, as stated by WebMD. Pregnant women, young children and women who are breastfeeding should avoid it due to a lack of adequate research. Speak to a qualified medical professional before using arnica gel.