Modified-release drug products

"Many terms are used to describe modified-release products including extended-release, prolonged-release, controlled-delivery, slow-release and sustained-release. These preparations, by definition, have a reduced rate of release of active substance. In general, these terms are interchangeable.



Delayed-release products are modified-release, but by definition are not extended-release. They involve the release of discrete amount(s) of drug some time after drug administration, e.g. enteric-coated products, and exhibit a lag time during which little or no absorption occurs...



Extended-release products contain a higher drug load and thus any loss of integrity of the release characteristics fo the dosage form has potential problems. While some extended-release products can be divided to provide half-d0ses..., others should only be taken whole... Modified-release products should never be crushed or chewed as the slow-release characteristics may be lost and toxicity may result. This is particularly important in patients unable to swallow whole tablets, a problem commonly affecting the elderly. The larger size of extended-release products may cause difficulties in ingestion or transit through the gut. These problems may result in some drugs... causing local tissue damage in patients who have a pathological or drug-induced reduction in gut motility."



Source: Oral extended-release products by Lloyd N. Sansom, Head, School of Pharmacy and Medical Sciences, University of South Australia, Adelaide

(http://www.australianprescriber.com/magazine/22/4/88/90/)

Drug products that should not be broken, divided, chewed or crushed

Bisacodyl (Dulcolax) 5 mg Enteric Coated Tablet

Mfr./Dist: Interphil Labs., Inc.

Butamirate Citrate (Sinecod Forte) 50 mg Sustained-release Tablet

Mfr./Dist.: Interphil Labs., Inc./Novartis

Felodipine (Versant-XR) 5 mg Extended Release Tablet

Mfr./Distr.: Standard Chem.& Pharm.Co., Ltd./United Labs., Inc./L.R. Imperial, Inc.

Ferrous Sulfate (Sorbifer Durules) 500 mg Sustained Release Tablet

Mfr.: AstraZeneca

Furosemide 40 mg/Potassium Chloride 600 mg (Diumide-K) Continus Tablet (Controlled-Release)

Mfr./Dist: NAPP Lab., Inc/Pascual/Mundipharma

Gliclazide (Glubitor-OD) 30 mg Modified-Release Tablet

Mfr./United Lab., Inc./L.R Imperial, Inc.)

Nifedipine (Adalat GITS 30) 30 mg Extended Release Tablet

Mfr.: Bayer AG/Bayer Phils., Inc.

Nifedipine (Calcibloc OD) 30 mg Coated Tablet

Mfr.: Bayer AG/Bayer Phils., Inc./Therapharma

Oxycodone HCl (Oxycontin) 10 mg, 20 mg, 40 mg, 80 mg Controlled-Release Tablets

Mfr./Dist: Bard Pharmaceuticals, Ltd.Mundipharma/Pascual/Zuellig Pharma Corp.

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Drug products that may be divided (split) but should not be chewed or crushed

Isosorbide-5-Mononitrate (Imdur Durules) 30 mg and 60 mg Sustained Release Tablets

Mfr.: AstraZeneca

Theophylline (Theo-Dur) 200mg and 300 mg Sustained-Release Tablets

Mfr./Dist.: Valpharma S.A./AstraZeneca

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Note: The above list is incomplete.