Evaluation of the use of tolvaptan in a Spanish tertiary hospital

• Published in: European journal of hospital pharmacy. Science and practice Vol. 19; no. 2; pp. 184 - 185
• Main Authors: Folguera, C., Saavedra, V., Torralba, A.
• Format: Journal Article
• Language: English
• Published: London BMJ Publishing Group LTD 01.04.2012
• Subjects: Cardiology; Drug dosages; Endocrinology; Gastroenterology; Hyponatremia; Internal medicine; Nephrology
• ISSN: 2047-9956; 2047-9964
• DOI: 10.1136/ejhpharm-2012-000074.263

Background Tolvaptan is the first oral antagonist of the vasopressin V2 receptor, indicated in adult patients with hyponatraemia secondary to syndrome of inappropriate antidiuretic hormone hypersecretion (SIADH). Purpose To evaluate the use of tolvaptan in a Spanish tertiary hospital. Materials and methods Retrospective observational study of the use of tolvaptan from November 2009 to October 2011. The authors identified patients who had received treatment with tolvaptan during the study period. A data collection sheet was designed on which was recorded: diagnosis related to hyponatraemia, age, gender, dose, duration of treatment, serum sodium when the treatment with tolvaptan was initiated and time until normalisation of serum sodium. Results Four of the 15 patients identified (mean age of 68±17.8 years; 60% males) were admitted to the Internal Medicine ward, 4 to Gastroenterology, 4 to Cardiology, 1 to Endocrinology and 1 to Nephrology. Four patients had hyponatraemia related to oedematous decompensation secondary to liver disease, in 4 the cause was heart failure, while 6 patients were diagnosed with SIADH and in the other 2 patients, hyponatraemia was secondary to the use of drugs. The dose usually used was 15 mg/day, although 5 patients took 30 mg/day and in one case, the maximum dose specified in the summary of product characteristics (SPC), 60 mg/day, was reached. The duration of treatment varied from 3 to 7 days or 1-2 months in patients on Internal Medicine and Gastroenterology, to 6 months in Endocrinology, Nephrology and Cardiology patients. 6 patients died due to their severe clinical situation. No side effects related to tolvaptan were recorded. Conclusions Our results agree with the tolvaptan clinical trials, that it appears to be safe and effective in the treatment of hyponatraemia refractory to other treatments. Although there were no side effects related to tolvaptan, it is likely that some of the adverse effects described in the SPC may have been masked by the patient's clinical status.