Aseptic mucositis is a regularly occurring complication during radiochemotherapy of head and neck cancer. In case of a superinfection with pathogenic microorganisms the degree of mucositits can make an interruption of cancer therapy imperative. It may also cause severe complications such as fulminating fatal infection, local spreading to the oesophagus and even mediastinitis as well as disseminated fungal infections. We investigated the effect of the systematic local combined application of H202, povidone iodine, nystatine and dexpanthenol solution for the prophylaxis and therapy of mucositis induced by radiochemotherapy. During 16 months of application of our scheme symptoms of mucositis appeared only to a minor extent. No interruption of radiochemotherapy was necessary at any time.