Excipient Effect on Drug Absorption in Humans

Open to people ages 18-64

1. Healthy volunteers of all ethnic groups and races.
2. Male and females between the ages of 18-64 years old, inclusive.
3. Subjects who are willing to avoid ingestion of fruit juices and citrus bioflavonoids, such as grapefruit extract, hesperidin supplement and naringin supplement, for a period extending from one week prior to the initiation of the study until its completion.
4. Written informed consent obtained from the subject and ability for subject to comply with the requirements of the study.

1. Subjects with extreme obesity (BMI > 35).
2. Subjects who are allergic to fexofenadine or SLS.
3. Subjects who have hemoglobin level lower than 12 g/dL.
4. Subjects who are pregnant, breastfeeding, or unwilling to practice birth control during participation in the study.
5. Subjects consuming types of food and supplements with the potential to interfere with the study objectives as judged by the Investigator.
6. Subjects taking any drugs, especially known OATP2B1 substrates (aliskiren, atenolol, celiprolol, fexofenadine, rosuvastatin and ticlopidine, etc.) except birth control hormonal medications.
7. Subjects with a condition, disease, or abnormality that in the opinion of the Investigator would compromise the safety of the patient or the quality of the data.
8. Subjects with any disease affecting or impairing the function of the liver, kidney or heart.
9. Subjects with gastrointestinal disease, gastrointestinal disorder, or gastrointestinal surgery.
10. . Subjects with known infection with HIV, Hepatitis B or Hepatitis C (as determined by questionnaire, no laboratory diagnostics concerning these diseases will be performed within the present study). Volunteers who are cured of past Hepatitis C infection are eligible to participate with a doctor's approval letter).
11. . Subjects who are smokers or have smoked in the past year and/or have smoked or ingested tetrahydrocannabinol/marijuana in the past week, or who are unwilling to comply throughout the study period.
12. . Alcohol use on average > 2 servings/day or > 14 servings/wk (Serving size: 12oz beer/4oz wine/2oz hard liquor) in the past week or self-reported binge drinking.
13. . Participating in another research study while participating in this research study.
14. . Non-English speaking.
15. . Subjects with abnormal laboratory results at Screening Visit as judged by the Investigator or study physician.