Botulinum toxin A (BTX-A) injections to the salivary glands are effective in the treatment of drooling, and complications are rare. However, there are only a few previous reports on the long-term use of BTX-A injections. This study retrospectively analyzes our experience of treating drooling with repeated BTX-A injections in patients with neurodegenerative diseases. All patients who received repeated BTX-A injections to the submandibular glands at Tampere University Hospital in 2004-2013 were included in the analysis. Six patients, aged from 6 to 21 years, were included in the study, and a total of 41 bilateral BTX-A injections were administered to their submandibular glands. The average number of injections per patient was 6 (range: 3-11). The average interval between the injections was 9.8 months (range: 4-18), and 95% (39/41) of the injections were performed with good response. The complication rate of the BTX-A injections was 2.4% (1/41), since one of the patients had swallowing problems after an injection. BTX-A injections to the submandibular glands are effective and have a low morbidity rate, and repeated injections can be recommended as long-term treatment of drooling.