Abstract Background Endoscopic thoracic sympathectomy (ETS) is an effective treatment for palmar hyperhidrosis and has been extended to craniofacial symptoms such as blushing and facial sweating. Adverse effects, including compensatory sweating, may cause patients to regret surgery. Such adverse events are currently unpredictable. This study investigated whether age, sex or bodyweight influenced the outcome. Methods A total of 110 patients who had bilateral ETS for palmar hyperhidrosis or facial symptoms (blushing or sweating) were asked to complete a questionnaire before and after surgery regarding physical and emotional symptoms, and overall satisfaction. Results Seventy-nine useable questionnaires were obtained. A decrease (an improvement) in physical symptom score was found in all patients; the median (interquartile range) change was − 15 (−9 to − 18) for facial symptoms and − 8 (−6·75 to − 9) for palmar symptoms. Similarly, there was an improvement in emotional symptom score of − 16 (−8 to − 28) for facial symptoms and − 13 (−7·25 to − 18·5) for palmar symptoms. More compensatory sweating was noted in those treated for facial symptoms (P = 0·007). There was no influence of age, sex or body mass index on outcome. Conclusion ETS is an effective treatment for palmar and facial symptoms. Side-effects may be worse in patients treated for facial symptoms.