Fig. 2 —Case 1. Certain symptoms are attenuated following treatment with low-dose naltrexone (LDN) in a long-standing case of CRPS (6 years after onset). a. Allodynia is greatly reduced in both legs after LDN. However, bilateral trophic changes remain in the lower extremities. Slight swelling is present in the distal portion of the right foot. Within 2 months of treatment with LDN, the patient was able to bear full body weight, and walk without assistance. Before LDN, the patient utilized a cane for 6 years. b. One year after LDN treatment, the patient still has persistent long-term trophic changes in the skin of both lower extremities (taken 1/16/2013)
Transdermal patches (adhesive patches placed on the skin) may also be used to deliver a steady dose through the skin and into the bloodstream. Testosterone-containing creams and gels that are applied daily to the skin are also available, but absorption is inefficient (roughly 10%, varying between individuals) and these treatments tend to be more expensive. Individuals who are especially physically active and/or bathe often may not be good candidates, since the medication can be washed off and may take up to six hours to be fully absorbed. There is also the risk that an intimate partner or child may come in contact with the application site and inadvertently dose himself or herself; children and women are highly sensitive to testosterone and can suffer unintended masculinization and health effects, even from small doses. Injection is the most common method used by individuals administering AAS for non-medical purposes.