In this study we explored the potential effects of concomitant intake of ethanol on drug absorption. We focused on the effect on solubility and measured the gastric concentration reached at elevated ethanol levels. The data were analyzed together with previous data from simulated intestinal fluids using the computational simulation tool GI-Sim. It was found that non-ionized and lipophilic compounds were likely to have higher solubility in gastrointestinal fluids when ethanol was present and for these, Anticancer Compound Library cell line concomitant intake of ethanol increased the absorption. If such compounds also have narrow therapeutic windows, the concomitant ethanol intake results in a higher risk of ADRs.
Financial support from The Swedish Research Council (Grants 621-2008-3777 and 621-2011-2445) and the Swedish Medical Products Agency is gratefully Panobinostat acknowledged. We are also thankful to biorelevant.com for providing the SIF original powder used in the dissolution experiments and to Simulations Plus (Lancaster, CA) for providing the Drug Delivery
group at the Department of Pharmacy, Uppsala University, with a reference site license for the software ADMET Predictor. We thank Elin Jern for skillful experimental assistance with solubility measurements. “
“The magnitude of oral drug absorption and systemic availability are consequences of the interplay between parameters related to the drug itself, drug product (formulation), study condition and the system, i.e., the human body. Hence, drug-specific physicochemical and biopharmaceutical characteristics, together with anatomical and physiological factors, will determine a drug’s oral bioavailability (F) in a given scenario. F is the product of the fraction of the drug that is absorbed (fa) and the fractions that escape from pre-systemic metabolism in both the gut wall (FG) and the liver (FH) ( Lin et al., 1999). Formulation characteristics can play a critical role in the drug absorption process. This applies in particular for drugs for which dissolution, solubility and/or permeability
characteristics represent the limiting steps for oral absorption, namely, drugs that do not belong to class 1 in the Biopharmaceutics Classification System (BCS) (Amidon et al., 1995 and Wilding, 1999). The BCS defines four classes based 17-DMAG (Alvespimycin) HCl on a compound’s aqueous solubility and intestinal permeability (high solubility and high permeability (class 1), low solubility and high permeability (class 2), high solubility and low permeability (class 3), low solubility and low permeability (class 4)) (Amidon et al., 1995). In general, the selection of a specific formulation is based on its minimal negative impact on the drug absorption rate, i.e., immediate release (IR) formulations. However, there are circumstances for which controlling the release rate of the drug from the formulation into the gastrointestinal (GI) lumen is desirable (Langer, 1990).