Objective: To describe the characteristics of weight gain occurring on children treated for migranous conditions with pizotifen.
Design: Retrospective case note review
Setting: West Suffolk Hospital between 1999 and 2003
Patients: 405 clinic attendances of 121 children receiving Pizotifen treatment
Main outcome measures: Rates of change in weight for age z-score between successive outpatient appointments were used to detect excessive weight gain.
Results: The mean rate of weight z-score increase for 105 patients receiving a constant dosage in 181 intervals between appointments was 0.79 standard deviations per year compared with 0.11 standard deviations per year for height z-score increases. The rate of weight z-score increase was not correlated with pizotifen dose per kg (r-.0.08), per m2 (r=-0.05) or initial BMI (r=-0.04). Mean rates of z-score increase were similar in patients with a satisfactory and unsatisfactory therapeutic responses.
Conclusions: Excess weight gain in Pizotifen therapy is not predicted by drug dosage or therapeutic response within the range of doses used in clinical practice.