Effect of pilocarpine hydrochloride on salivary production in previously irradiated head and neck cancer patients

Abstract

Objective: To study the effects of pilocarpine hydrochloride on whole salivary gland production in Mexican patients affected by hyposalivation secondary to radiotherapy of the head and neck region.

Study design: With previous written informed consent, 20 patients affected by hyposalivation secondary to head and neck radiation therapy (>40 Gy) were evaluated through the whole saliva test (WST) before, during and after ten weeks of treatment with pilocarpine hydrochloride (5 mg t.i.d.). Hyposalivationrelated symptomatology was assessed before and at every week by means of a questionnaire with an ordinal scale ranging from 0-10. Salivary production values recorded at the end of the study and those obtained before treatment were compared by means of student's t test. A paired Wilcoxon test was used to compare the differences in the oral symptoms, such as oral dryness, soreness, ability for speaking and swallowing before and after treatment.

Results: Initial WST had a mean salivary production of 0.8 cm (s.d. 0.7), with a range from 0 to 2.9 cm). After ten weeks of treatment salivary production increased to a mean of 2.24 cm (s.d. 0.7), with a range from 1.2 to 4.0 cm. There was a salivary flow increase of 64.5% (p<0.001). In addition, there were significant improvements in oral dryness, mouth comfort, ability to speak and ability to swallow (p<0.01). Adverse effects were usually minimal and they did not cause withdraw from the study in any case.

Conclusions: Administration of 5-mg pilocarpine hydrochloride tablets three times daily significantly improved salivary production and clinical symptomatology secondary to radiation-induced hyposalivation with minimal side-effects. In addition, this study showed that WST is a fast, technically simple and highly reliable method to study salivary production in prospective studies.