Induction of CYP1A2 activity by carbamazepine in children using the caffeine breath test

Br J Clin Pharmacol. 1998 Feb;45(2):176-8. doi: 10.1046/j.1365-2125.1998.00684.x.


Aims: Carbamazepine is a known enzyme inducer. The aim of this study was to determine whether carbamazepine induces the metabolism of caffeine in children.

Methods: Children due to receive carbamazepine for epilepsy were recruited into the study. The caffeine breath test was carried out prior to the administration of carbamazepine and after a minimum of 2-3 weeks therapy. Five children were studied and they received 200-600 mg carbamazepine daily.

Results: The mean values of the 2 h cumulative labelled carbon dioxide were 3.47% before and 7.65% during carbamazepine. There was a significant increase in the percentage labelled caffeine exhaled as carbon dioxide during the administration of carbamazepine (Student's paired t-test, P < 0.05).

Conclusions: The results suggest that carbamazepine induces the metabolism of caffeine by the CYP1A2 pathway in the children studied.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Analgesics, Non-Narcotic / administration & dosage
  • Analgesics, Non-Narcotic / pharmacology*
  • Analgesics, Non-Narcotic / therapeutic use
  • Breath Tests / methods*
  • Caffeine* / metabolism
  • Carbamazepine / administration & dosage
  • Carbamazepine / pharmacology*
  • Carbamazepine / therapeutic use
  • Carbon Dioxide / metabolism
  • Central Nervous System Stimulants / pharmacology*
  • Child
  • Cytochrome P-450 CYP1A2 / drug effects*
  • Cytochrome P-450 CYP1A2 / metabolism
  • Dose-Response Relationship, Drug
  • Drug Interactions
  • Epilepsy / drug therapy
  • Female
  • Humans
  • Male
  • Respiration / drug effects


  • Analgesics, Non-Narcotic
  • Central Nervous System Stimulants
  • Carbon Dioxide
  • Carbamazepine
  • Caffeine
  • Cytochrome P-450 CYP1A2