Food affects Zidovudine concentration independent of effects on gastrointestinal absorption.

Food can change drug concentrations by several mechanisms, including some that are independent of absorption effects. This study tests the hypothesis that a meal decreases zidovudine (ZDV) concentration in blood plasma independent of an effect on drug absorption. The study was conducted as a substudy nested in a larger protocol in which ZDV was given to 7 healthy men by continuous infusion for 5 days starting on day 1.

Hyperosmolar sexual lubricant causes epithelial damage in the distal colon: potential implication for HIV transmission.

Background: Many sexual lubricants are hyperosmolar. Hyperosmolar enemas induce epithelial damage, and enema use has been associated with an increased risk of HIV infection. To inform the development of rectal microbicide formulation, we evaluated the effects of hyperosmolar gels on the rectal mucosa.

The effect of isotretinoin on the pharmacokinetics and pharmacodynamics of ethinyl estradiol and norethindrone.

Background: Isotretinoin is a known teratogen, and when it is prescribed to women of childbearing potential, 2 forms of contraception must be used, commonly including hormonal contraception. Although isotretinoin and estradiol are metabolized largely by cytochrome P450 (CYP) 3A4 and glucuronidation, the potential for clinical drug interaction, with subsequent pharmacodynamic impact, has not been evaluated.

Methods: We enrolled 26 healthy women who were to receive isotretinoin for the treatment of severe, recalcitrant nodular acne and who were taking or planning to take oral contraceptives.