Capsule Formats May Hamper Green Tea Catechin Bioavailability

Improving a drug's stability in the gastrointestinal (GI) tract is paramount for enhancing its bioavailability and therapeutic effectiveness. Various strategies are employed to protect the drug from the harsh gastric milieu and to ensure its release and absorption at the desired site within the GI tract.Polymer coatings are one such method used to shield drugs from the stomach's acidic environment. By preventing premature drug release, these coatings improve the bioavailability of unstable...

Bioequivalence in generic drugs, such as tablets and capsules, refers to their pharmaceutical equivalence to the brand-name counterparts. However, for therapeutic equivalence, manufacturers must also consider physical attributes like size, shape, and weight (FDA Guidance for Industry, December 2003). Discrepancies in these aspects could impact patient compliance and cause medication errors. For instance, swallowing difficulties, often experienced with larger tablets or capsules, can lead to...

Bioavailability refers to the proportion of an administered drug that reaches the systemic circulation in its active, unaltered form. It is a crucial pharmacokinetic parameter that determines the effectiveness of a drug in achieving its intended therapeutic outcomes. The route of administration significantly influences bioavailability, with intravenous administration achieving 100% bioavailability as the drug directly enters the bloodstream. In contrast, oral administration often results in...

Bioavailability refers to the proportion of an unaltered drug that, after administration, enters the systemic circulation and can be distributed to the desired action site. Factors such as gastrointestinal (GI) absorption and liver biotransformation influence the bioavailability of a drug when it is administered orally. When a drug is administered intravenously, it enters the systemic circulation directly; by definition, its bioavailability is assumed to be 100%. The bioavailability of an...

Modified-release (MR) dosage forms are designed to extend drug release over time, thereby maintaining stable plasma concentrations and reducing dosing frequency. However, their bioavailability is typically below 100% due to incomplete drug release and presystemic metabolism, and limitations in drug permeability across the gastrointestinal epithelium, all of which can restrict the fraction of the drug reaching systemic circulation. Consequently, studying the in vivo bioavailability of MR...

Bioavailability refers to the extent and rate at which a drug reaches systemic circulation in its active form. Extent refers to the amount of the drug that makes it into circulation, while rate is the speed at which it enters circulation. It is influenced by several factors critical for optimizing drug formulations, dosing regimens, and therapeutic outcomes.Physicochemical properties of drugs and formulationsThe solubility, stability, and dissolution rate of a drug significantly impact its...