Adverse radiation effects (AREs) can occur after stereotactic radiosurgery (SRS), and symptomatic cases are often treated with corticosteroids, pentoxifylline, and vitamin E. The supplement 5-Loxin (Boswellia serrata) is an extract of Indian frankincense that inhibits vascular endothelial growth factor expression and has been shown to reduce perilesional edema in brain tumor patients undergoing fractionated radiation.

Three patients underwent SRS for meningioma or metastasis and developed symptomatic AREs at 4 to 8 months. They were initially treated with corticosteroids, pentoxifylline, and vitamin E with transient improvement followed by recurrent neurological symptoms and imaging findings as steroids were tapered off. All patients were rescued by the administration of 5-Loxin with resolution of neurological symptoms and imaging changes, discontinuation of steroids, and no medication side effects.

The author's early experience with 5-Loxin has been encouraging, and this supplement has become the author's first-line treatment for acute radiation effects after SRS. The author reserves bevacizumab for significant mass effect or failure of oral therapy. 5-Loxin has many advantages including low cost, ease of use, and patient tolerability. More experience is needed to confirm the role of 5-Loxin in the upfront treatment of AREs.