Evaluation of CYP2C9 Activity

The Use of Phenytoin Metabolic Ratio as a Putative Marker of CYP2C9 Activity In-vivo

The use of phenytoin metabolism to produce S-HPPH accounts for more than 85% of its metabolism. This metabolic pathway is mediated by the activity of CYP2C9.

The purpose of the present study is:

1. To confirm the use of phenytoin metabolic ratio as a marker of CYP2C9 activity
2. To correlate phenytoin metabolic ratio with CYP2C9 genotype
3. To study the frequency distribution of CYP2C9 activity in-vivo

Inclusion Criteria:

• Age range of 20-50 years old
• Absence of significant disease states

Exclusion Criteria:

• The presence of significant disease states
• The use of drugs (including birth control pills)