Summary: This prospective randomized trial demonstrated a significant reduction in oral radiation mucositis (ulceration) in pet dogs receiving radiation therapy for nasal tumors when dogs were given a glutamine containing suspension compared to a standard daily mouthwash. The use of the glutamine suspension was not associated with any adverse effects in dogs and did not alter the activity of the radiation therapy in the treated dogs.

Publication: Khanna C, Klausner JS, Walters P, Bell FW, James K, Lund E, Redic K, Anderson PM. L-glutamine versus placebo in the prevention of radiation induced oral mucositis. In Vivo. In progress.

Background: Oral mucositis is a common complication of radiation therapy of the head and neck. Radiation-induced mucositis of the oral cavity results in patient discomfort and may adversely affect treatment outcomes. Mucositis can lead to interruptions or early stoppages in planned radiation treatments and negatively impact on nutritional status. L-glutamine, an important fuel source for gastrointestinal epithelial cells, may decrease the severity of mucositis associated with radiation therapy. Using a relevant animal model, we evaluated of the radio-protective activity of an oral l-glutamine suspension in preventing oral mucositis.

Methods: Pet dogs, receiving radiation therapy for nasal cancers, were entered to a randomized double-blind placebo-controlled trial to evaluate an oral suspension of l-glutamine in the prevention of radiation-induced mucositis. The l-glutamine suspension, or a corn starch placebo, in a sugar-based vehicle was administered to dogs orally (4.0 gm/m2/d of l-glutamine or an equivalent volume of placebo suspension). Dogs were evaluated daily for the severity of mucositis based on a clinical grading score and a food intake score. The severity of mucositis, the duration of mucositis, and the number of interruptions (due to mucositis) in the planned radiation therapy was compared for the dogs receiving the l-glutamine and placebo oral suspension.

Results: A significant decrease in the number of interruptions in radiation therapy was seen in the dogs receiving l-glutamine compared to placebo (p=0.028). Furthermore dogs receiving l-glutamine had a significant decrease in the number of days of severe mucositis compared to the dogs receiving placebo (p=0.05). There were no adverse effects associated with administration of the l-glutamine suspension
Conclusions: Amelioration of oral radiation induced-mucositis is possible using an oral suspension of l-glutamine. Further controlled clinical trials of the radio-protective properties of l-glutamine are warranted.