Check out Swanson's vitamins, Mountain Rose Herbs, Native American Nutritionals or your local health food store.
Known as the "King of Oils" Frankincense is widely regarded as one of the most versatile and beneficial essential oils in the world. There is a reason the Wise Men brought this special oil to baby Jesus; it's value and benefits can't be ignored. So many, in fact, you should read about them here: http://www.organicfacts.net/health-benefits/essential-oils/health-benefits-of-frankincense-essential-oil.html
This oil is very valuable, both fiscally and to your body. It is expensive but it works. The best variety is from the Oman region.
Personally I've benefitted from using Frankincense in multiple ways. I suffer from Tarsal Tunnel Syndrome due to nerve and ligament damage sustained in the Army. I use Frankincense daily on my ankles and the bottoms of my feet. I notice if I forget to use it because I end up in a world of hurt. Sometimes I use this oil as a perfume and it makes me happy.
Researchers from Japan and the University of Maryland both determined that Frankincense oil has anti-inflammatory properties. Studies have shown that the boswellic acids in Frankincense have an anti-inflammatory action much like the conventional nonsterodial anti-inflammatory drugs (NSAIDS) used for many inflammatory conditions. It also benefits both osteo- and rheumatoid arthritis. Frankincense is a safe and effective treatment for asthma, inflammatory bowel diseases, ulcers and indigestion. Additional benefits include muscle relaxation, immune stimulation, uplifting mood and heightening awareness.
Most importantly, it helps to regenerate nerves and supports healthy respiratory function. When diffused it can be beneficial with bronchitis, headaches and pneumonia.
**How we use it for SMA: Add to coconut oil or fragrance-free lotion and use as a muscle rub.