The objective of the study was to evaluate patient benefit and health-related quality of life after use of botulinum neurotoxin (BoNT) A for various otorhinolaryngological, functional (non-cosmetic) indications. The design consisted of a survey study of a patient cohort (n = 40) treated with BoNT A for functional indications. Patients were asked to answer the Glasgow Benefit Inventory (GBI), a retrospective questionnaire well validated for measuring the effect of otorhinolaryngological interventions on the health-related quality of life. GBI scores can range from -100 (maximal adverse effect), through 0 (no effect), to 100 (maximal positive effect). A total of 29 patients (72.5%) returned a valid questionnaire. Mean total GBI scores for the particular indications were 1.2 (sialorrhea, n = 7), 22.6 (gustatory sweating, n = 8), 20.6 (palatal tremor, n = 5), 15.0 (postlaryngectomy voice disorders due to pharyngoesophageal spasm, n = 5), 38.9 (adductor spasmodic dysphonia, n = 2) and 27.8 (oromandibular dystonia, n = 2), showing a mean overall positive effect of BoNT A treatment on the health-related quality of life, respectively. A varying percentage of patients reported an increase in their health-related quality of life, indicated by positive total GBI scores: sialorrhea 28.6%, gustatory sweating 87.5%, palatal tremor 60%, postlaryngectomy voice disorders 60%, spasmodic dysphonia 100% and oromandibular dystonia 100%. Use of BoNT A can be considered an effective therapeutic option for all the indications investigated. However, the possibility of raising patients' health-related quality of life with this kind of therapy varies significantly for different indications. Further studies are needed to analyze the patients who will benefit most from a treatment with BoNT A.