Oral administration of indomethacin has been limited by its poor water solubility. Cyclodextrins have been recognized as potential candidates to overcome the poor solubility of indomethacin through the formation of inclusion complexes. The aim of our study was to compare the dissolution profiles of pure indomethacin and its mixtures with α- and γ-cyclodextrins The inclusion complexes of indomethacin with α- and γ-cyclodextrins were prepared by direct mixing in dissolution vessel. Fixed volumes of the dissolution medium were withdrawn at 0,5; 1 and 4 hours. Dissolution tests were performed on the USP Apparatus 2, rotating speed 100 rpm at 37±0.5 ° C, 500 ml, distilled water and 0,1 M HCl solution). Quantification of dissolved indomethacin was performed by UV/VIS spectrophotometric method at the absorption maximum around 320 nm. The results were expressed as relative dissolution rate (ratio between indomethacin dissolved from its physical mixtures with α- and γ-cyclodextrins and that dissolved the pure drug). Relative dissolution rates of indomethacin in combination with α- and γ-cyclodextrins at the end of testing were in the range of 91,66 to 337,14 % (for α- cyclodextrin) and in the range of 128,57 to 301,92 % (for γ-cyclodextrin). The complexation of indomethacin with α- and γ-cyclodextrins resulted in the enhancement of dissolution rate.

Amlodipine is a long-acting calcium channel blocker used in the treatment of hypertension and angina pectoris. [...]

The objective of this work was to compare several profiles of dissolution data for metoprolol controlled release tablet formulations in order to identify possible changes in dissolution profiles of whole and scored tablets. Adequate design of score lines (on one or both sides) as well as the technology of preparation of tablet mixtures ensure forming a score line of adequate thickness, shape, size, curvature. According to the obtained results, this type of extended release formulation is eligible for splitting and use in therapy either as a whole or scored tablets.

Dissolution rate of two fluoroquinolone antibiotics (ciprofloxacin and moxifloxacin) was analysed in presence/absence of three antacid formulations. Disintegration time and neutralisation capacity of antacid tablets were also checked. Variation in disintegration time indicated the importance of this parameter, and allowed evaluation of the influence of postponed antacid-fluoroquinolone contact. The results obtained in this study showed decreased dissolution rate of fluoroquinolone antibiotics from tablets in simultaneous presence of antacids, regardless of their type and neutralisation capacity.

Tablets are one of the most popular and preferred solid dosage forms because they can be accurately dosed, easily manufactured and packaged on a large scale, have good physical and chemical stability, and can contribute to good patient compliance given their ease of administration. The ability to match doses to patients depends on the availability of multiple dose sizes and adequate dose-response information. These are not always provided, so splitting of the tablets is sometimes necessary. Tablet splitting is an accepted practice in dispensing medication. It has been used when a dosage form of the required strength is not available commercially. The aim of our study was to compare some physical parameters of whole and scored lisinopril and lisinopril/hydrochlorthiazide tablets and to accept or exclude their influence on the obtaining of required dosage. According to the results obtained, we may conclude that tablets from batch "I", "II", "III" and "IV" satisfied pharmacopeial requirements concerning crushing strength, friability, disintegration time and mass uniformity. The hardness testing showed acceptable reproducibility and indicate that the data variation was primarily from the irreversible changes in the structure of tablet samples. The act of compacting powders stores energy within the tablets, by shifting or compressing the intermolecular bonds within the particles. The tablets have a natural tendency to relax once pressure is removed, and this tendency works against the interparticle bonding formed during compression. Hardness testing procedure causes irreversible changes in this structure.

Anthocyanins are effective antioxidants but they have also been proposed to have other biological activities independent of their antioxidant capacities that produce health benefits. Examples range from inhibition of cancer cell growth in vitro, induction of insulin production in isolated pancreatic cells, reduction of starch digestion through inhibition of a-glucosidase activity, suppression of inflammatory responses as well as protection against age-related declines in cognitive behavior and neuronal dysfunction in the central nervous system. However, to achieve any biological effect in a specific tissue or organ, anthocyanins must be bioavailable; i.e. effectively absorbed from the gastrointestinal tract (GIT) into the circulation and delivered to the appropriate location within the body. In this study, we assess the stability of anthocyanins from commercial Black currant (Ribes nigrum L.) juice using an in vitro digestion procedure that mimics the physiochemical and biochemical conditions encountered in the gastrointestinal tract (GIT). The main objective of this work was the evaluation of stability of anthocyanins during in vitro digestion in gastric and intestinal fluid regarding whether appropriate enzyme (pepsin or pancreatin) was added or not. Anthocyanins present in commercial black currant juice remain stable during in vitro digestion in gastric fluid regardless whether pepsin was added into the medium or not. Also, they remain stable during in vitro digestion in simulated intestinal fluid without pancreatin. The stability studies of anthocyanins in the intestinal fluid containing pancreatin indicated reduced stability, which also mainly contribute to slight reduction of total anthocyanins content (-1.83%) in commercial black currant juice.

When considering single-dose preparations, it is fundamental that the patient receives in his individual dose an amount of drug close to that claimed on the label. Since drug content and content uniformity of single-dose preparations depend on a number of processes associated with their manufacture, it is obviously unrealistic to expect every unit of product to possess exactly the same amount of the active ingredient. For that reason, pharmacopeial standards and specifications have been established to provide limits for permissible variations in the amount of active ingredient of individual single-dose units. The aim of our study was to determine the applicability of content uniformity and dissolution variation test on ropinirole hydrochloride tablets. According to the results obtained, we may conclude that analyzed ropinirole hydrochloride tablets satisfied pharmacopeial requirements concerning content uniformity and dissolution testing. In this case RSD tended to increase with the decrease of the labeled strength. It is obvious from the R2 value, as well. On the other side, if consider larger number of lots, analyzed by different assay methods and various sample preparation procedures this correlation is less pronounced. This may be a consequence of different assay techniques applied, HPLC, UV-D1 or UV.

Stability testing of an active substance or finished product provides information of the variation of drug substance or final product with time influenced by a variety of environmental factors such as temperature, humidity and light. Knowledge gained from stability studies enables understanding of the effects of the environment on the drugs. The aim of our study was to determine the stability of cefuroxime axetil oral suspension at different temperature storage conditions (stored at room /20 degrees C/ and refrigerated /5 degrees C/ conditions). Determination of cefuroxime (as cefuroxime axetil) was performed by dissolution testing. Fractions of the released cefuroxime axetil were compared using f2 value. After interpolating data for dissolution profiles at room and refrigerated conditions the following f2values were obtained: 62,56; 56,32 and 36,18 on 3rd, 6th and 10th day, respectively. These values indicate similarities in drug release from analyzed cefuroxime axetil oral suspension on 3rd, 6th day, and differences on 10th day. Based on our results, we may assume that cefuroxime axetil oral suspension preserves its stability for 10 days after reconstitution under room and refrigerated conditions. It is obvious, according to the f2 value obtained on the 10th day, that there is a difference between the released cefuroxime axetil from oral suspension at room (87,68%) and refrigerated (92,35%) conditions. Concentration changes can be caused by the mechanisms associated with drug release and hydrolytical decomposition of the sample and higher temperatures during longer period of storage.

Dose-related adverse effects of medications are a major problem in modern medical practice. The "correct" dose, based on drug company guidelines in package inserts, may not be correct for many patients. Tablet splitting or dividing has been an accepted practice for many years as a means of obtaining the prescribed dose of medication. As model tablets for this investigation, two batches of lisinopril- hydrochlorothiazide scored tablets labeled to contain 20/12.5 mg were used. The aim of this study was to establish possible influence of tablet splitting on content uniformity of lisinopril/hydrochlorthiazide tablets. Determination of the content uniformity of lisinopril and hydrochlorthiazide in our batches, was carried out by HPLC method. The results of content uniformity studies for halves of tablets containing combination of lisinopril-hydrochlorthiazide (supposed to contain 50% of stated 20/12.5 mg in the whole tablet) were: 49.60 +/-3.29% and 49.29+/-0.60 % (lisinopril); 50.33+/-3.50% and 50.69+/-1.95% (hydrochlorthiazide) for batch I and II, respectively. We can conclude that the results obtained in this study support an option of tablet splitting, which is very important for obtaining the required dosage when a dosage form of the required strength is unavailable, and for better individualization of the therapy.