Sustained-release tablets

Cosmetics and Pharmaceuticals. The main use of hexadecanol (cetyl alcohol) is in cosmetics (qv) and pharmaceuticals (qv), where it and octadecanol (stearyl alcohol) are used extensively as emoUient additives and as bases for creams, Hpsticks, ointments, and suppositories. Octadecenol (oleyl alcohol) is also widely used (47), as are the nonlinear alcohols. The compatibiHty of heavy cut alcohols and other cosmetic materials or active dmg agents, their mildness, skin feel, and low toxicity have made them the preferred materials for these appHcations. Higher alcohols and their derivatives are used in conditioning shampoos, in other personal care products, and in ingested materials such as vitamins (qv) and sustained release tablets (see Controlled RELEASE technology). 

If gastrointestinal upset occurs, take the drug with food. Do not chew or crush coated or sustained-release tablets. 

When tiie drug is given orally, the nurse instructs the patient not to chew the capsule or tablet but to swallow it whole For faster absorption, the drug is given with a full glass of water when the patient s stomach is empty, either 1 hour before or 2 hours after meals. If gastrointestinal upset occurs, the nurse can administer the drug with or immediately after meals. Sustained-released tablets should not be crushed or divided. 

Remember that the wax matrix of sustained-release tablets of procainamide (Procan SR only) is not absorbed by the body and may be found in the stool. This is normal. 

Do not chew or divide sustained-released tablets. Swallow them whole... 

Nunthanid, J., Laungtana-Anan, M., Sriamornsak, R, Limmatvapirat, S., Puttipipatkhachorn, S., Lim, L. Y. Khor, E. (2004). Characterization of chitosan acetate as a binder for sustained release tablets. Journal of Controlled Release, Vol. 99, 1, (September 2004), pp. (15-26), ISSN 0168-3659... 

Wellbutrin SR Yes Sustained-release tablet 150 300-400 Twice daily... 

Often it is unnecessary to calculate an exact value for an absorption rate constant. For example, when several oral tablets containing the same drug substance are all found to be completely absorbed, it may be sufficient to merely determine if the absorption rates are similar to conclude that the products would be therapeutically equivalent. In another instance, it would be possible to choose between an elixir and a sustained-release tablet for a specific therapeutic need without assigning accurate numbers to the absorption rate constant for the two dosage forms. 

Marvola, M., Aito, H., Pohto, P., Kannikoski, A., Nykanen, S., Kokkonen, P., Gastrointestinal transit and concomitant absorption of verapamil from a single-unit sustained-release tablet, Drug Dev. Ind. Pharm. 1987, 13, 1593-1609. 

Tramadol should be initiated at a lower dose (100 mg/day in divided doses) and may be titrated as needed for pain control to a dose of 200 mg/ day. It is available in a combination tablet with acetaminophen and as a sustained-release tablet. 

Costa P, Sousa Lobo JM. Influence of dissolution medium agitation on release profiles of sustained-release tablets. Drug Dev Ind Pharm 2001 27 811-817. 

Recently, Yoshikawa et al. [70] reported a new in vitro dissolution test, called the rotating beads method, for drugs formulated in pressure-controlled colon delivery capsules. This dissolution method was applied to acetominophen sustained-release tablets and two other drugs having low solubility in the colon, tegafur and 5-ASA. There was good correlation between the in vitro dissolution rates and the in vivo absorption rates. 

A VALIDATED ROBOTIC SYSTEM EOR DISSOLUTION ASSAY OE AN IMMEDIATE-RELEASE/SUSTAINED-RELEASE TABLET... 

The dissolution method for the immediate-release/sustained-release tablet requires the following parameters USP paddle method, 900 ml of water, SO rpm paddle speed, 37°C, and samphng points at 20 minutes, 40 minutes, 1, 2, 4, 6, 8 and 10 hours. Robotically, ahquots (8 ml) were removed, filtered through a 10 jm polyethylene filter and transferred to the storage rack. The volume (8 ml) was replaced with heated media. The samples were assayed hy HPLC using the external standard method. 

Weight Dose every 3 hours (standard formulation) Dose every 6 hours (standard formulation and sustained release) Dose every 12 hours Procanbid sustained release tablets only)... 

Angina patients maintained on the nifedipine capsule formulation may be switched to the sustained release tablet at the nearest equivalent total daily dose. Experience with doses more than 90 mg in angina is limited. 

Sustained release tablets - 75 mg once/day, in mid-morning. PHENDIMETRAZINE TARTRATE ... 

Controlled/Extended/Sustained-release tablets/capsules Relief of moderate to severe pain in those who require continuous, around-the-clock opioid therapy for an extended period of time. Not intended as an as-needed analgesic. 

Theophylline, a dimethylxanthine, causes broncho-dilation, possibly by inhibiting the enzyme phosphodiesterase in smooth muscle of the bronchioli. An other proposed mechanism of action is that of adenosine receptor antagonism. It has positive chronotropic and inotropic, CNS stimulant and weak diuretic properties. In obstructive lung disease sustained release tablets are to be preferred. Theophy-line has a narrow therapeutic index. Therapeutic plasma concentrations are between 7-15 mg/1. Theophylline undergoes N-demethylation via CYPl A2 in the liver and is eliminated in the urine as metabolites... 

Empty wax core from sustained-release tablets may appear in stool this is harmless... 

The time courses of the plasma concentrations of the oxime with the two types of tablets were fairly similar, the peak concentrations being attained at the same time after ingestion. The peak concentrations after the rapid-release tablets were somewhat above those produced by the same total amounts of II in the sustained-release tablets and the descent from the peak concentration was less precipitous after the sustained-release tablets than after the rapid-release ones. Oral doses of I (form not specified) produced peak plasma concentrations of oxime sooner after ingestion than after Ingestion of the tablets of II the peak plasma concentration from a given dose of I usually was larger than that from a similar dose of II in the form of... 

Te Wierik, G. H. P, Eissens, A. C., Bergsma, J., Arends, A. W., Lerk, C. F. (1997b). A new generation of starch products as excipient in pharmaceutical tablets. It. High surface area retrograded pregelatinized potato starch products in sustained-release tablets. J. Contr. Re/., 45,25-33. 

Cellulose disintegrants have been studied as insoluble matrices for sustained release tablets. Anionically charged carboxymethyl cellulose (sodium salt) was found to be inferior to methyl cellulose and poly(vinyl pyrollidone) as a binding agent for oxyphenbutazone tablets [291], However sodium carboxymethyl cellulose has found application as a dispersing agent for ibuprofen microspheres... 

For this sustained release tablet formulation, it was critical to match the dissolution profile in light of the changes in processing parameters. As shown below in Figure 24, the dissolution profiles at all speeds and hardness values were not significantly different. 

Cellulose derivatives, e.g. hydroxyethylcellulose, are used in the formulation of sustained release tablets and suspensions. Natrosol (hydroxyethylcellulose) is a nonionic water-soluble polymer that is extensively used as a thickener. 

The use of cellulose ethers in producing matrix-type sustained release tablets is well documented [7]. Hydrophilic matrices of ketoprofen with hydroxypropylmethylcellulose (KET-R)... 

Pan coating with a Eudragit-PEG 400 mixture proved to be best technique. The relative ease of manufacture and the variety of release profiles attainable make pan coating with a Eudragit E 300-PEG 400 mixture a useful technique for obtaining sustained release tablets. Further studies will be necessary to assess the influence of Eudragit PEG ratio on ketoprofen release characteristics. 

Oral 30, 60 mg tablets 180 mg sustained-release tablets 12 mg/mL syrup Parenteral 5 mg/mL for IM or slow IV injection Rivastigmine (Exelon)... 

Oral 100 mg tablets 100 mg sustained-release tablets Parenteral 30 mg/mL for IM, IV injection Riluzole (Rilutek)... 

Oral 75, 100 mg tablets 100, 150, 200 mg 12-hour sustained-release tablets 150, 300 mg 24-hour sustained-release tablets... 

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