Drug release from matrix tablets: physiological parameters and the effect of food

Abstract

Introduction: As dissolution plays an important and vital role in the drug-delivery process of oral solid dosage forms, it is, therefore, essential to critically evaluate the parameters that can affect this process. Areas covered:The consumption of food as well as the physiological environment and properties of the gastrointestinal tract, such as its volume and composition of fluid, the fluid hydrodynamics, properties of the intestinal membrane, drug dose and solubility, pK a , diffusion coefficient, permeability and particle size, all affect drug dissolution and absorption rate. There are several dissolution approaches that have been developed to address the conditions as experienced in the in vivo environment, as the traditional dissolution being a quality control method is not biorelevant and as such do not always produce meaningful data. This review also describes the development of a systematic way that differentiates between robust and non-robust formulations by varying the effects of agitation and ionic strength through the use of the automated United States Pharmacopeia type III Bio-Dis apparatus. Expert opinion:With the improved understanding of the physiological parameters that can affect the oral bioperformance of dosage forms, strides have, therefore, been made in making dissolution testing methods more bio-logically based with the view of obtaining more in vitro--in vivo correlations.Keywords: agitation rate, biodissolution, drug release, effect of food, hydrophilic matrices, ionic strength Highlights -Understanding all the physiological parameters can serve as a basis for designing dissolution testing methods and systems that can more fully represent the gastrointestinal (GI) tract in humans and allow more in vitro-in vivo (IVIVC) correlations to be obtained thereby improving the oral bioperformance of dosage forms.-Simulation of GI conditions is essential to adequately predict the in vivo behaviour of drug formulations.-The choice of appropriate media for in vitro tests is crucial to their ability to correctly forecast the food effect in pharmacokinetic studies.-Several methods of dissolution testing have been conducted and are still ongoing that seek to further understand and develop media and dissolution methods to better represent the in vivo conditions and to aid in the better prediction of in vivo drug release.-Systematic change of agitation method and ionic strength evaluation may be used as additional tools in allowing for the identification of potential fed and fasted effects on drug release from hydrophilic matrices in the drive for developing dissolution methodologies that are more relevant in helping to achieve more IVIVC.

Starch-free grewia gum matrices: Compaction, swelling, erosion and drug release behaviour

“…HPMC was used as a control due to its popular use in extended release matrices as a result of its robustness, stability, 140 regulatory acceptance and cost effectiveness (Tiwari and Rajabi-Siahboomi, 2008;Nokhodchi and Asare-Addo, 2014). In the present study HPMC K4M was chosen as it is a mid-range viscosity grade (~4000 cp) and is commonly used in matrix tablets (Ghori et al, 2014a).…”

Evaluation of sesamum gum as an excipient in matrix tablets

“…HPMC was used as a control due to its popular use in extended release matrices as a result of its robustness, stability, regulatory acceptance and cost effectiveness (Tiwari and Rajabi-Siahboomi, 2008;Nokhodchi and Asare-Addo, 2014). The matrix tablets containing theophylline as a model drug were formulated according to the unit formula in Table 1.…”

Drug release from E chemistry hypromellose tablets using the Bio-Dis USP type III apparatus: An evaluation of the effect of systematic agitation and ionic strength

“…Thus, in pH 1.2 agitation was 30 dpm, in pH 2.2 -25 dpm, in pH 5.8 -20 dpm, in pH 6.8 -15 dpm, in pH 7.2 -10 dpm and in pH 7.5 -5 dpm [20] *Ascending order of agitation; agitation was increased by 5 dpm every time the cylinder containing the drug moved from one vial to the other. Thus, in pH 1.2 agitation was 5 dpm, in pH 2.2 -10 dpm, in pH 5.8 -15 dpm, in pH 6.8 -20 dpm, in pH 7.2 -25 dpm and in pH 7.5 -30 dpm.…”

“…Furthermore, the physiological response to ingestion of food such as gastric acid secretion may increase of decrease the bioavailability of some drugs [11][12][13]. pH and ionic strength of the gastrointestinal (GI) fluids vary greatly along the GI tract under both fasted and fed conditions [14,15] and this can affect the rate at which a drug is released from hydrophilic extended release (ER) matrices [16][17][18][19][20]. The gel layer formed around hydrophilic matrices, upon its contact with GI fluids, is eroded allowing drug release.…”