The Biopharmaceutics Classification System is a system to differentiate the drugs on the basis of their solubility and permeability.[1] You can do this as many times as you wish, and at as many different locations you desire. (I personally live close to TWO different stores and I do this all the time. Unless you 'roam' the card over to your location, you will never have access to what is on the card! 'ROAMING' a card over to a different location is an EXTREMELY IMPORTANT thing you HAVE to do if you are given a card by someone who used it previously at a different location, or if you purchased a card from someone on eBay that has tickets and/or chips on it from another location. One day I will play at one location, and the next time I want to go to the other one, but I have to 'roam' the card over to whichever location I am currently at in order for me to use that card and to have access to any chips, tickets, or whatever I may have on it. This system restricts the prediction using the parameters solubility and intestinal permeability. The solubility classification is based on a United States Pharmacopoeia (USP) aperture. The intestinal permeability classification is based on a comparison to the intravenous injection. All those factors are highly important because 85% of the most sold drugs in the United States and Europe are orally administered[citation needed]. BCS classes[edit]According to the Biopharmaceutical Classification System (BCS) drug substances are classified to four classes upon their solubility and permeability:[1]
Definitions[edit]The drugs are classified in BCS on the basis of solubility, permeability, and dissolution. Novel romantis dewasa. Solubility class boundaries are based on the highest dose strength of an immediate release product. A drug is considered highly soluble when the highest dose strength is soluble in 250 ml or less of aqueous media over the pH range of 1 to 7.5. The volume estimate of 250 ml is derived from typical bioequivalence study protocols that prescribe administration of a drug product to fasting human volunteers with a glass of water. Permeability class boundaries are based indirectly on the extent of absorption of a drug substance in humans and directly on the measurement of rates of mass transfer across human intestinal membrane. Alternatively non-human systems capable of predicting drug absorption in humans can be used (such as in-vitro culture methods). A drug substance is considered highly permeable when the extent of absorption in humans is determined to be 90% or more of the administered dose based on a mass-balance determination or in comparison to an intravenous dose. For dissolution class boundaries, an immediate release product is considered rapidly dissolving when no less than 85% of the labeled amount of the drug substance dissolves within 15 minutes using USP Dissolution Apparatus 1 at 100 RPM or Apparatus 2 at 50 RPM in a volume of 900 ml or less in the following media: 0.1 N HCl or simulated gastric fluid or pH 4.5 buffer and pH 6.8 buffer or simulated intestinal fluid. See also[edit]
References[edit]Bcs Class Iv Drugs
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Retrieved from 'https://en.wikipedia.org/w/index.php?title=Biopharmaceutics_Classification_System&oldid=884065387'
College of Pharmacy, University of Michigan, Ann Arbor, Michigan 48109-1065, Department of Pharmacy and Technology, University of Valencia, Valencia, Spain, Faculty of Pharmaceutical Sciences, Setsunan University, Osaka, Japan, and Center for Drug Evaluation and Research, Food and Drug Administration, Rockville, Maryland 20857
AbstractOrally administered, immediate-release (IR) drug products in the top 200 drug product lists from the United States (US), Great Britain (GB), Spain (ES), and Japan (JP) were provisionally classified based on the Biopharmaceutics Classification System (BCS). The provisional classification is based on the aqueous solubility of the drugs reported in readily available reference literature and a correlation of human intestinal membrane permeability for a set of 29 reference drugs with their calculated partition coefficients. Oral IR drug products constituted more that 50% of the top 200 drug products on all four lists, and ranged from 102 to 113 in number. Drugs with dose numbers less than or equal to unity are defined as high-solubility drugs. More than 50% of the oral IR drug products on each list were determined to be high-solubility drugs (55â59%). The provisional classification of permeability is based on correlations of the human intestinal permeabilities of 29 reference drugs with the calculated Log P or CLogP lipophilicity values for the uncharged chemical form. The Log P and CLogP estimates were linearly correlated (r2 = 0.79) for 187 drugs. Metoprolol was chosen as the reference compound for permeability and Log P or CLogP. A total of 62â69.0% and 56â60% of the drugs on the four lists exhibited CLogP and Log P estimates, respectively, greater than or equal to the corresponding metoprolol value and are provisionally classified as high-permeability drugs. Saint seiya asgard full episodes. We have compared the BCS classification in this study with the recently proposed BDDCS classification based on fraction dose metabolism. Although the two approaches are based on different in vivo processes, fraction dose metabolized and fraction dose absorbed are highly correlated and, while depending on the choice of reference drug for permeability classification, e.g., metoprolol vs cimetidine or atenolol, show excellent agreement in drug classification. In summary, more than 55% of the drug products were classified as high-solubility (Class 1 and Class 3) drugs in the four lists, suggesting that in vivo bioequivalence (BE) may be assured with a less expensive and more easily implemented in vitro dissolution test. Keywords: BCS; solubility; dose number; permeability; partition coefficient; WHO essential drugs; top-selling US, European, Japanese drugs; BDDCS This article is cited by 280 publications.
So I had an exam today in which one of the questions was in what class (I-IV) of the Biopharmaceutical Classification System (BCS) the drug nifedipine falls in. Class I drugs are considered highly soluble and highly permeable, class II badly soluble and highly permeable, class III highly solube and badly permeable and class IV badly soluble and badly permeable. Solubility The aqueous solubility of a drug substance is considered as high according to the HHSFDA BCS criteria when:
Permeability According to HHS-FDA a drug is considered a highly permeable, when more than 90% of the orally administered dose is absorbed in the small intestine.[1] Obviously judging from literature it falls under BCS class II and you'd probably assume so if you look at the solubility (practically insoluble in water <1g/10000ml) and the permeability, which is good because it is absorbed well (>90%). [2] However the way the question was asked was interesting because of the information given. It explicitly said that a dose of 20 mg was the maximum dose and no exact solubility was given except that the solubility was 'practically insoluble', meaning a solubility of < 1 g/ 10000 ml. Now whether the solubility is 1g /10001 ml or 1g/ 100002 ml, nobody knows.. The extent of absorption given was 90% and thus high permeability was assumed. However when you calculate how much volume of water is needed to let this fully dissolve, you'd come with the answer 0,02 * 10000 = 200 ml water. This is smaller than 250 ml and thus one would be inclined to then assume the solubility is high according to the specifications stated above, which would lead you to think the drug falls under BCS class I. Of course in reality you'd have to take into account the exact solubility which probably isn't exactly 1 g/10000 ml and the exact volume of the gastrointestinal tract which probably isnt exactly 250 ml. Now what am I supposed to believe in this situation? In this case the dose plays an important role in determining the BCS class and thus answering the question. Would you in this case have taken the rules for what they are and follow them like I did, taking into account dose and assuming the lowest solubility or would you have based it purely on the 'practical insolubility in water' of the drug and conclude low solubility and thus BCS class II?Maybe I'm thinking too hard about this, but I'm curious if anyone has something to say on this.I personally think it would've been fair if the exact solubility (perhaps even a fictive solubility) of nifedipine and exact volume of GIT were given in this situation to make this question more clear. Sources:
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1 Answer$begingroup$The tl;dr answer is that, as the question is worded (and without an actual copy of the question or the data provided to you), its not possible to definitively assign a BCS class. Nifedipine is a class II drug: class II is low solubility and high permeability. Formulation typically is used to enhance solubility of compounds in this class. The data in your question is a little confusing, but you state that the compound is 'practically insoluble' which means that it must be either class II or class IV (practically insoluble definitely suggests low solubility). With the information provided (i.e. nothing about permeability), you cannot distinguish between II and IV. Permeability, whilst often correlated to solubility, is not directly linked, such that you cannot attempt (as I think you have tried) to calculate one based on the other (how permeable something is depends upon structure, and whether it can get through the membrane).
NotEvans.NotEvans.
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