P-gp is one of the main efflux transporters at the blood-brain barrier and is responsible for the transport of a variety of neurotoxic substances, including pharmaceuticals. Multiple studies report gender differences in therapeutic outcomes, toxicity and side effects for many drug agents. P-gp plays an important role in the bio-availability, drug distribution, metabolism and elimination of pharmaceuticals labelled as P-gp substrates (e.g. the majority of antidepressants and antipsychotics). A difference in P-gp function was already reported in hepatic P-gp expression. The aim of the current study is to evaluate the influence of gender on cerebral P-gp function. Outcomes of this study can be of great importance in gender-based prescription of P-gp substrate pharmaceuticals.

Inclusion Criteria:

• Healthy volunteers

Exclusion Criteria:

• Use of medication with a known effect on the BBB P-glycoprotein transporter
• Any history of neurological or psychiatric conditions affecting the BBB P-glycoprotein function