Respiratory tract secretions (RTS), the sound created by poorly-cleared mucous in the hypopharynx or bronchial tree, can be alarming for dying patients, relatives and staff. Increased knowledge into the etiology of RTS and its response to treatment is needed to improve future management. We studied retrospectively the data from 202 patients who died on a 30-bed specialist palliative care unit during a one-year period. These patients were observed every four hours during the dying phase. RTS was treated with hyoscine hydrobromide. Ninety-nine patients (49%) developed RTS. The median time from onset of RTS till death was 16 hours. Fifty-nine patients could have their treatment response assessed. Of these, 30.5% responded within four hours, 33.9% after four hours, and 35.5% died with RTS. Increasing the dose for nonresponders had no significant effect. Significant risk factors for developing RTS were found to be prolonged dying phase, primary lung cancer and male gender.