Electronic measurement of compliance with mercaptopurine in pediatric patients with acute lymphoblastic leukemia

Med Pediatr Oncol. 1998 Feb;30(2):85-90. doi: 10.1002/(sici)1096-911x(199802)30:2<85::aid-mpo3>3.0.co;2-w.


Twenty-four pediatric patients with acute lymphoblastic leukemia (ALL) on maintenance therapy were evaluated for their compliance with taking their prescribed doses of oral mercaptopurine (6-MP).

Procedure and results: We utilized the Medication Event Monitoring System (MEMS; Aprex Corporation, Fremont, CA) for the study. Compliance was defined as the number of days doses were taken as a percentage of the total number of days doses were prescribed during the study period. The mean age of the patients was 7.3 years (range 2.6-17.2 (years). Patients were evaluated for a mean of 44 days (range 15-94 days). Thirty-three percent of patients (8) took less than 90% and 17% (4) took less than 80% of their prescribed pills. Eight patients were also evaluated for a difference in compliance between morning and evening administration. For the comparison of compliance between a morning vs. an evening schedule a tren toward improved compliance in the evening was found. Five patients had an increase and one patient a decrease in compliance with an evening schedule (differences ranged from 0.2% to 51.3%), with two patients having 100% compliance on both schedules.

Conclusions: Our data raise concern that a significant proportion of pediatric patients are non-compliant with pill taking and demonstrate that the timing of administration of 6-MP in children with ALL may be crucial in some patients and supports the hypothesis that evening administration of 6-MP is associated with a lower risk of relapse.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Antimetabolites, Antineoplastic / therapeutic use*
  • Child
  • Child, Preschool
  • Computers
  • Female
  • Humans
  • Male
  • Mercaptopurine / therapeutic use*
  • Patient Compliance*
  • Precursor Cell Lymphoblastic Leukemia-Lymphoma / drug therapy*


  • Antimetabolites, Antineoplastic
  • Mercaptopurine