1. The aim of the study was to assess the effect of glycopyrrolate on drooling in an adult male patient with cerebral palsy. 2. After a thorough medical examination and consent in writing by the responsible guardian, a baseline sum score for frequency and seriousness of drooling was established over a 2 week period in addition to data on shifts of handkerchiefs, urination, defecation and observation of behaviour. Glycopyrrolate (1 mg) tablets were then administered, starting with one tablet daily the third week and increasing the daily dose by one tablet per week until a maximum of four tablets during week six and 4 days of week seven when the daily dose was reduced to two tablets for 3 days. For the four weeks 8-11 three tablets were given daily. In week 12 the dose was reduced to two tablets and for the weeks 13-15 no tablets of glycopyrrolate were given. 3. For as long as the patient received three to four tablets of glycopyrrolate daily, drooling was markedly reduced and handkerchiefs were not necessary on some days. After the tablets were withdrawn drooling increased to approximately the same level as it was before treatment. No adverse medical, psychological, or social effects were observed. 4. For shorter periods, glycopyrrolate can be given in controlled doses provided that an adequate medical assessment has been undertaken.