title: A role for CYP in the drug-hormone crosstalk of the brain.
abstract: BACKGROUND
  Libido disorders, menstruation problems, perception and cognition deficiencies are potentially undesired, but clinically emerging, side effects after long-term therapy with antiepileptic drugs or chemotherapeutic agents. These disorders were shown to occur predominantly in patients who had taken drugs interacting with the CYP system of the brain, particularly in the hippocampus, the hypothalamus, the cerebellum or in the amygdala. CYPs present and active in these regions usually inactivate steroid hormones such as testosterone.
  
  
  METHODS
  The present review focuses on recent concepts of brain CYP function, gives an outlook on neuroactive drug use in therapy and self-medication, and highlights the endocrine side effects after drug therapy in neurological diseases and brain tumors.
  
  
  RESULTS
  The reader is introduced to a CYP mediated drug-hormone crosstalk as a possible mechanism to explain these side effects.
  
  
  CONCLUSIONS
  The drug-hormone crosstalk may be of considerable importance in the assessment of neuroactive drugs and future drug design.
authors.affiliation: Medizinische Fakultät der Universität Freiburg, Breisacherstrasse 64, Freiburg, Germany. ralf.meyer@uniklinik-freiburg.de
authors.forename: Ralf Peter
authors.initials: RP
authors.lastname: Meyer
authors.forename: Marcel
authors.initials: M
authors.lastname: Gehlhaus
mesh_terms: D000818:Animals; D001921:Brain / Q000201:enzymology / Q000378:metabolism*; D003577:Cytochrome P-450 Enzyme System / Q000378:metabolism*; D064420:Drug-Related Side Effects and Adverse Reactions; D012739:Gonadal Steroid Hormones / Q000378:metabolism*; D006801:Humans; D004364:Pharmaceutical Preparations / Q000378:metabolism*
chemical_list: D012739:Gonadal Steroid Hormones; D004364:Pharmaceutical Preparations; D003577:Cytochrome P-450 Enzyme System