We are reporting the use of a xylocain test before the injection of botulinal toxin within the "facial paralysis and botulinal toxin" multidisciplinary consultation of the Caen regional hospital. Our assessment is about 16 patients tested. This test is based on a digital film and a questionnaire. It is often proposed when toxin is first used. It influences the patient's choice. It permits a better understanding of the toxin action by the patient, it reassures. It is reliable for the practitioner even though we do not have a mathematical correlation between the xylocain volume and the botulinal toxin volume. Simple and far, it is a help for the patient and the practitioner before a delicate injection of botulinal toxin.