Controlled release tablet

The past decade has seen a dramatic increase in the number of reported applications of neural computing in pharmaceutical formulation [29-32]. Applications now cover a variety of formulations—for example, immediate and controlled release tablets, skin creams, hydrogel ointments, liposomes and emulsions, and film coatings. The following examples are by no means exhaustive, but they show where neural computing has been used successfully in modeling formulations. 

Designed experimentation, involving mostly some type or modification of factorial design, has been used to study many different types of formulation problems. These include a pharmaceutical suspension [21], a controlled-release tablet formulation [22], and a tabletcoating operation [23]. In the latter case, Dincer and Ozdurmus studied an enteric film coating and utilized the steepest descent graphic method to select the optimum. 

As a general rule, do not divide sustained/controlled release medications as they may lose their controlled release properties. However, there may be some exceptions to this rule. For example, Calan SR 240 tablets which are to be given once daily can be split to administer 120 mg (or A tablet) twice daily. Therefore, unless specifically suggested by the manufacturer, controlled release tablets should not be crushed or broken. 

The provision of rate-controlled drug action (such as various controlled-release tablets, capsules, and suspensions)... 

D. Impurity Testing of a Controlled-release Tablet with Two APIs... 

TABLE 2 Composite Assay Data of Controlled-release Tablets Using Various Solidhandling and Extraction Techniques... 

FIGURE 6 HPLC chromatogram of an extract of a controlled-release tablet with one API showing the extraction efficiency between whole tablets by sonication and crushed tablets by shaking and sonication. 

Swallow controlled-release tablets whole do not bite or divide. 

Controlled-release tablets Management of moderate to severe pain when a continuous, around-the-clock analgesic is needed for an extended period of time. Not intended for use as a as-needed analgesic. 

Not indicated for pain in the immediate postoperative period (the first 12 to 24 hours following surgery), or if the pain is mild or not expected to persist for an extended period of time. Oxycodone controlled-release tablets are only indicated for postoperative use if the patient is already receiving the drug prior to surgery or if the postoperative pain is expected to be moderate to severe and persist for an extended period of time. Individualize treatment, moving from parenteral to oral analgesics as appropriate. 

May be taken with or without food. Swallow controlled-release tablets whole, do not chew or crush. Administer as a single daily dose, usually in the morning. Patients not responding to a 20 mg dose may benefit from dose increases in 10 mg/day increments (12.5 mg/day controlled release) at intervals of at least 1 week. 

Fig. 11. Cumulative mean diuresis versus cumulative mean furosemide excretion following 60 mg doses given as two controlled release tablets (boxes), as plain tablets (closed triangles) and following an intravenous dosage of 0.5 mg/kg (open triangles). (From Paintaud G. Kinetics of drug absorption and infiuence of absorption rate on pharmacological effect. Diss. Karolinska Institutet, Stockholm 1993, reproduced by permission.)...

Do not break, chew, or crush controlled-release tablets (OxyContin)... 

Oral 2.5, 5 mg capsules 5, 10 mg controlled-release tablets Nicardipine (generic, Cardene)... 

Oral 400 mg tablets and controlled-release tablets Note Pentoxifylline is labeled for use in intermittent claudication only. 

Chitosan Controlled release tablets, dissolution aid and disintegrant Repeat-dose toxicity (10 days in rabbit) No toxicity reported 33... 

Special solid oral dosage forms are the controlled-release tablets. In some cases, it is desirable that the release of the drug from the tablet should be more gradual than in the normal case. This controlled slow release can be achieved in different ways. 

Jacob, J., Pharmacokinetics of bioadhesive, gastroretentive, controlled release tablets of itraconazole (Spherazole CR) in beagle dog model. Controlled Release Society 33rd Annual Meeting and Exposition, 2005. 

Katikaneni, P.R., et al. 1995. Ethylcellulose matrix controlled release tablets of a water-soluble drug. Int J Pharm 123 119. 

Buccoadhesive-controlled release tablets for delivery of nifedipine were prepared by direct compression of carboxymethyl cellulose (CMC) with carbomer (CP) and compared to those prepared with PVP, PVA, HPMC, and acacia by a modified tensiometry method in vitro. It was found that the adhesion force was significantly affected by the mixing ratio of CP CMC in the tablets. CMC is necessary for controlling the release rate, whereas CP is important in providing bioadhesion. The tablets containing 15% CMC and 35% CP were found to have optimum drug release rate and bioadhesion [81]. 

Schwarz, J., Lee, M., Weisspapir, M., Zhang, Q., and Lu, W. Increased bioavailability of coenzyme Q-10 in self-emulsifying controlled release tablet New type of delivery system for hydrophobic drugs. Int. Symp. Contr. Rel. Bioact. Mater. 28 824—825, 2001. 

This time controlled release tablet with a designated lag time followed by a rapid release may provide an alternative to site-specific delivery of drugs with optimal absorption windows or colonic delivery of drugs that are sensitive to low pH or enzyme action for the treatment of localized conditions such as ulcerative colitis, Crohn s disease, and irritable bowel syndrome (IBS). Also, by controlling a predetermined lag time of drug from dosage form, the release behavior can be matched with the body s circadian rhythm pattern in chronotherapy. 

K. Lehmann, Formulation of controlled release tablets with acrylic resins Acta Pharm Fenn 93 55-74 (1984). 

Sustained/controlled release tablets Chewable tablets Orally disintegrating tablets... 

GlaxoSmithKline. (2007, August). Paxil CR (paroxetine hydrochloride) controlled-release tablets. Prescribing Information. Retrieved from www.GSK.com... 

Controlled-Release Tablet by Direct Compression and Wet Granulation... 

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