Unlike propranolol, atenolol does not pass through the blood-brain barrier thus avoiding various central nervous system side effects. This proved that results were significant. The microstructure is constantly changing, making these very dynamic systems with reversible droplet coalescence .
New modes of delivering a drug to the eye are being actively explored ranging from a solid hydrophobic device which is inserted into the ophthalmic cul-de-sac, to conventionally applied dosage forms which, due to their formulation characteristics markedly increase the drug residence time in the orbit of the eye, thus providing drug for absorption for prolonged period of time and reducing the frequency with which a given drug product must be administered .
The determined parameters were the pupillary diameter and variation of intra-ocular pressure. Tapping was continued until no further change in volume was noted. This may be because of the mobility of polymer chains was very dependent on the water content of the system.
Surfactants are surface-active molecules. Five formulations were made using each method. Where Q t is the amount of drug released at time t and K H is the Higuchi release rate constant; this is, the most widely used model to describe drug release from pharmaceutical matrices.
Bicontinuousmicroemulsions, as mentioned before, may show non-Newtonian flow and plasticity. Numerous antihypertensive drugs, from a variety of pharmacologic classes and with different mechanisms of action, have been shown in randomized controlled trials to reduce cardiovascular morbidity and mortality, and it can be concluded that it is blood pressure reduction, and not some other pharmacologic property of the drugs, that is largely responsible for those benefits.
All the physical and in vitro tests were performed and any significant changes were observed.
The first factor effecting drug availability is that the loss of the drug from the palpebral fissure. The swelling index was calculated by the following equation: Over time, they will begin to separate back into their two phases.
Drug- excipients interactions play a vital role with respect to release of drug from the formulation amongst others. The spectrum of pure atorvastatin calcium was equivalent to the spectra obtained by the addition of superdisintegrants [ 22 ].
In a placebo controlled comparison of approximately equipotent oral doses of several beta blockers, atenolol produced a significantly smaller decrease of FEV1 than nonselective beta blockers such as propranolol and, unlike those agents, did not inhibit bronchodilation in response to isoproterenol.
The reduction of IOP at four h after medication was 6. It was observed that as we increase the concentration of Carbopol P and the viscosity of the hydrophilic polymers the water uptake capacity increased which results in an increase of swelling index.
Instrumentation and their application to microemulsions will be discussed in a later chapter.
Warnings Cardiac Failure Sympathetic stimulation is necessary in supporting circulatory function in congestive heart failure, and beta blockade carries the potential hazard of further depressing myocardial contractility and precipitating more severe failure. One tablet from each formulation was weighed and kept in petri dish containing 15 ml of 0.
The prepared tablets were evaluated for physical characteristics, bioadhesive strength, buoyancy lag time, swelling index and in vitro drug release studies. The hydrodynamic balanced system HBS is also called floating drug delivery system FDDS is an oral dosage form capsule or tablet designed to prolong the residence time of the dosage form within the GIT.
In the present study 16 formulations with different concentration of polymer were prepared and evaluated for physico-chemical parameters, in-vitro buoyancy studies, in-vitro release studies and stability studies.
The wetting time of the sublimed formulations was less due to the presence of camphor in their composition than other two methods. Opthalmic products, like most others in the medical armamentarium, are undergoing a process termed optimization. The results of both wetting time and disintegration time studies were in agreement indicating that all formulations would definitely disintegrate in oral cavity within specified time period [ 26 ].
Where K 1 is the first order release constant; in this case, the drug released at each time is proportional to the residual drug inside the dosage form.
One tablet from each formulation was weighed and kept in petri dish containing 15 ml of 0. Several possible mechanisms have been proposed and include: In this case, microemulsions are not obtained spontaneously. It represents that wetting volume for tablets depends upon the method of preparation and concentration of superdisintegrants.
DSC analysis was conducted to analyze any possible drug-drug and drug-superdisintegrants interactions by using thermal analyzer SDT.
These results of powder blend were well within identified limits as shown in Table 2. Opthalmic products, like most others in the medical armamentarium, are undergoing a process termed optimization.
Some evidence suggests that even in normal doses the most frequently used? Due to the spontaneous formation of the microemulsions, they can be prepared in one step by mixing the constituents with magnetic stirrer. This corresponds to an average change from the pretreatment value of 22 percent.The final optimized formulation (FM2) released % of Atenolol in 12hrs.
The floating lag time and log time of optimized sustained layer showed min and above 12hr respectively. Formulation and evaluation of gastro retentive floating drug delivery system of Atenolol Composition of different formulations Formulation No.
Atenolol (mg) HPMC K15M (mg) HPMC KM (mg) NaHCO 3 (mg) Mag. Stearate (mg) Talc adjusted to ml with N HCl. Further 1ml of the above. All the sixteen formulation of prepared floating tablets of Atenolol were subjected to in-vitro release studies these studies were carried out using dissolution apparatus, N Hcl (pH ).
The kinetic values obtained for formulation F12 and F16 were shown in Table 5. In all the formulations, the amount of atenolol was kept constant at 50 mg.
The polymers like Carbopol p, HPMC K4M, HPMC K15M, and HPMC KM were used in different concentrations in combination. Total weight of the tablet was kept constant at mg. The formulae of different floating bioadhesive tablets of atenolol are given in Table 1.
EVALUATION OF ATENOLOL CORE (AT2) AND PRESS COATED (HE) TABLETS Spectrophotometric estimation of atenolol Atenolol was estimated by UV visible. Formulation and evaluation of buccoadhesive tablets of Atenolol Prasad B Kadam* 1, Remeth J Dias 1, Kailas K Mali 1, Vijay D Havaldar 1 and Niranjan S Mahajan 1.Download