Gastroretentive dosage forms for prolonging gastric residence time

International Journal of Pharmaceutical Medicine

Volumn 21, Issue 2, 2007, Pages 157-171

  Kumar, Ritesh ^a   Philip, Anil ^a  

^a Rajiv Academy for Pharmacy ^*  (India)

Author keywords

[No Author keywords available]

Indexed keywords

ACICLOVIR; ALLOPURINOL; AMOXICILLIN; ANTACID AGENT; BENSERAZIDE PLUS LEVODOPA; CAPTOPRIL; CHLORDIAZEPOXIDE; CHLORPHENIRAMINE; CIFRAN OD; CIPROFLOXACIN; CONVIRON; DIAZEPAM; FAMOTIDINE; FERROUS SULFATE; FUROSEMIDE; GAVISCON; ION EXCHANGE RESIN; LEVODOPA; LIQUID GAVISCON; METOPROLOL; MISOPROSTOL; NITROFURANTOIN; OFLIN OD; OFLOXACIN; PARACETAMOL; PROPRANOLOL; RANITIDINE; RIBOFLAVIN; SALBUTAMOL; SOTALOL; TETRACYCLINE; UNCLASSIFIED DRUG; VERAPAMIL;

DRUG ABSORPTION; DRUG BIOAVAILABILITY; DRUG DELIVERY SYSTEM; DRUG DOSAGE FORM; DRUG RELEASE; DRUG SOLUBILITY; DRUG STABILITY; HUMAN; HYDROGEL; LIPOSOMAL DELIVERY; NONHUMAN; PRIORITY JOURNAL; REVIEW; STOMACH; STOMACH EMPTYING; WATER TRANSPORT;

EID: 34248220006     PISSN: 13649027     EISSN: 14735679     Source Type: Journal    
DOI: 10.2165/00124363-200721020-00005     Document Type: Review

References (135)

1. Garg S, Sharma S. Gastroretentive drug delivery systems [online]. Available from URL: http://www.touchbriefings.com/pdf/17/pt031_p_garg.pdf [Accessed 2005 May 20]
2. Chawla G, Gupta P, Koradia V, et al. Gastroretention: a means to address regional variability in intestinal drug absorption. Pharm Tech 2003 July; 27 (7): 50-68
3. Lee TWY, Robinson JR. Controlled release drug delivery system. In: Gennaro AL, editor. Remington: the science and practice of pharmacy. Philadelphia (PA): Philadelphia College of Pharmacy and Science, 2000: 903-29
4. Chien YW. Oral drug delivery and delivery systems. In: Chien YW, editor. Novel drug delivery systems. New York: Marcel Dekker, 1992: 139-96
5. Rouge N, Buri P, Doelker E. Drug absorption sites in the gastrointestinal tract and dosage forms for site-specific delivery. Int J Pharm 1996; 136: 117-39
6. Vyas SP, Khar RK. Gastroretentive systems. In: Vyas SP, Khar RK, editors. Controlled drug delivery: concepts and advances. 1st ed. New Delhi: Vallabh Prakashan, 2005: 196-218
7. Ashford M. The gastrointestinal tract physiology and drug absorption. In: Aulton ME, editor. Pharmaceutics: the science of dosage form design. 2nd ed. New York: Churchill Livingstone, 2002: 217-27
8. Gupta PK, Robinson JR. Oral controlled-release delivery. In: Kydonieus A, editor. Treatise on controlled drug delivery. New York: Marcel Dekker, 1992: 255-310
9. Tayade P. Gastroretentive drugs: a review, 2003 [online]. Available from URL: http://www.expresspharmapulse.com/20030417/ndds1.shtml [Accessed 2005 Mar 18]
10. Klausner EA, Lavy E, Friedman M, et al. Expandable gastroretentive dosage forms. J Control Rel 2003; 90: 143-62
11. Hejazi R, Amiji M. Stomach specific anti H. pylori therapy: preparation and characterization of tetracycline of a floating multiple-unit capsule, a high density loaded chitosan microspheres. Int J Pharm 2002; 235: 87-94
12. Sawicki W. Pharmacokinetics of verapamil and nor verapamil from controlled release floating pellets in humans. Eur J Pharm Biopharm 2002; 53: 29-35
13. Nim KH, Singh BN. Drug delivery: oral route. In: Swarbrick J, Boylan JC, editors. Encyclopedia of pharmaceutical technology. Vol 1. 2nd ed. New York: Marcel Dekker, 2000: 886-907
14. Boulton DW, Fawcett JP, et al. Enantioselective disposition of albuterol in humans. Clin Rev Allergy Immunol 1996; 14: 115-38
15. Hoter D, Dreessman JB. Influence of physiochemical properties on dissolution of drugs in the gastrointestinal tract. Adv Drug Del Rev 1987; 25 (1): 3-14
16. Sato Y, Kawashima Y, Takeuchi H, et al. In vivo evaluation of riboflavin-containing microballoons for floating controlled drug delivery system in healthy human volunteers. J Control Rel 2003; 93 (1): 39-47
17. Groning R. Control of release and biological availability of drugs: investigations into the renal elimination of nitrofurantoin. Int J Pharm 1981; 8: 175-81
18. Whitehead L, Collett JH, Fell JT. Amoxycillin release from a floating dosage form based on alginates. Int J Pharm 2000; 210 (1): 45-9
19. Dave BS, Amin AV, Patel MM. Gastroretentive drug delivery system of ranitidine HCl formulation and in vitro evaluation. AAPS Pharm Sci Tech 2004; 5 (2) 34: 1-10 [online]. Available from URL: http://www.aaps.pharm.sci.tech.org/ [Accessed 2005 Apr 10]
20. Nur AO, Zhang JS. Captopril floating and/or bioadhesive tablets: design and release kinetics. DDIP 2000; 26 (9): 965-9
21. Hejazi R, Amiji M. Stomach-specific anti-H. pylori therapy: II, gastric residence studies of tetracycline-loaded chitosan microspheres in gerbils. Pharm Dev Technol 2003; 8 (3): 253-62
22. Fell JT. Targeting of drugs and delivery systems to specific sites in the gastrointestinal tract. J Anat 1996; 189: 517-9
23. Menon A, Ritschel WA, Sakr A. Development and evaluation of a monolithic floating dosage form for furosemide. J Pharm Sci 1994; 83 (2): 239-45
24. Bardonnet PL, Faivre V, Pugh WJ, et al. Gastroretentive dosage forms: overview and special case of Helicobacter pylori. J Control Rel 2006; 111: 1-18
25. Hwang SJ, Park H, Park K. Gastric retentive drug delivery systems. Crit Rev Ther Drug Carr Sys. 1998; 15 (3): 243-84
26. Singh BN, Kim KH. Floating drug delivery systems: an approach to oral controlled drug delivery via gastric retention. J Control Rel 2000; 63 (1-2): 235-59
27. Deshpande AA, Rhodes CT, Shah NH, et al. Controlled release drug delivery systems for prolonged gastric residence: an overview. Drug Dev Ind Pharm 1996; 22 (6): 531-9
28. Ali J, Ahuja A, Khar RK. Controlled drug delivery system. In: Ali J, Ahuja A, Khar RK, editors, Dosage form design. 1st ed. New Delhi: Birla Publications, 2005: 168-229
29. Arora S, Ali J, Ahuja A, et al. Floating drug delivery systems: a review. AAPS Pharm Sci Tech 2005; 06 (03): E372-E390 [online]. Available from URL: http://www.aaps.pharm.sci.tech.org/ [Accessed 2005 Sep 20]
30. Caldwell LJ, Gardner CR, Cargill RC, inventors. Drug delivery device which can be retained in the stomach for a controlled period of time. Merck & Co., Inc., assignee. US Patent no. 4,735,804. 1988 Apr 5
31. Akiyama Y, Nagahara N, Nara E. Evaluation of oral mucoadhesive microspheres in man on the basis of the pharmacokinetics of furosemide and riboflavin, compounds with limited gastrointestinal absorption sites. J Pharm Pharmacol 1998; 50 (2): 159-66
32. Reddy LH, Murthy RS. Floating dosage systems in drug delivery. Crit Rev Ther Drug Carr Syst 2002; 19 (6): 553-85
33. Hoffman A, David S, Lavy E, et al. Pharmacokinetics and pharmacodynamic aspects of gastroretentive dosage forms. Int J Pharm 2004; 277: 141-53
34. Chawla G, Gupta P, Bansal AK. Gastroretentive drug delivery system. In: Jain NK, editor. Progress in controlled and novel drug delivery systems. 1st ed. New Delhi: CBS publishers, 2004: 79-81
35. Waergh A, Allison G. The digestive system. In: Waugh A, editor. Rose & Wilson anatomy and physiology in health and illness. 9th ed. Philadelphia (PA): Springer, 2005: 325-38
36. Chaurasia BD. Abdominal part of oesophagus and stomach. In: Singh I, editor. Human anatomy, regional and applied. 3rd ed. New Delhi: CBS publishers, 2000, 206-11
37. Feldman M, Barnett C. Fasting gastric pH and its relationship to true hypochlorhydria in humans. Dig Dis Sci 1991; 36: 866-9
38. Benini L, Brighenti F, Castellani G, et al. Gastric-emptying of solids is markedly delayed when meals are fried. Dig Dis Sci 1994; 39: 2288-94
39. Ganong WF. Regulation of gastrointestinal function. In: Review of medical physiology. 22nd ed. San Francisco (CA): McGraw-Hill, 2005: 479-512
40. Read NW, Sugden K. Gastrointestinal dynamics and pharmacology for the optimum design of controlled release oral dosage form. Crit Rev Ther Drug Carrier Syst 1987; 4 Suppl. 3: 221-63
41. Guyton AC, Hall JE. General principles of gastrointestinal function: motility, nervous control and blood circulation. In: Guyton AC, Hall JB, editors. Text book of medical physiology. 10th ed. Philadelphia (PA): WB Saunders, 2004: 718-26
42. Washington N, Washington C, Millon CG. The digestion and absorption of food. In: Washington N, Washington C, Millon CG, editors. Physiological barriers to drug absorption. 2nd ed. New York: Taylor and Francis, 2005: 75-103
43. Coupe AJ, Davis SS, Wilding IR. Variation in gastrointestinal transit of pharmaceutical dosage forms in healthy subjects. Pharm Res 1991; 8 (3): 360-4
44. Rocca DJG, Omidian H, Shah K. Progress in gastroretentive drug delivery systems. Business Briefing 2003: 152-155 [online]. Available from URL: http://www.b-briefings.com/ [Accessed 2005 Jul 3]
45. Hou SY, Cowles VE, Berner B. Gastric retentive dosage forms: a review. Crit Rev Ther Drug Carr Syst 2003; 20 (6): 459-97
46. Frieri G, Petris GD, Aggio A, et al. Gastric and duodenal juxtamucosal pH and Helicobacter pylori. Digestion 1995; 56 (2): 107-10
47. Devereux JE, Newton JM, Short MB. The influence of density on the gastrointestinal transit of pellets. J Pharm Pharmacol 1990; 42 (7): 500-1
48. Mazer N, Abisch E, Gfeller JC, et al. Intragastric gastrointestinal behavior and absorption kinetics of a normal and 'floating' modified-release capsule of isradipine under fasted and fed conditions. J Pharm Sci 1988; 8: 647-57
49. Clarke GM, Newton JM, Short MD. Gastrointestinal transit of pellets of differing size and density. Int J Pharm 1993; 100 (1-3): 81-92
50. Meyer JH, Dressman J, Fink AS, et al. Effect of size and density on gastric emptying of indigestible solids. Gastroenterology 1985; 88: 1502-7
51. Goldschmiedt M, Barnett CC, Schwarz BE. Effect of age on gastric acid secretion and serum gastric concentrations in healthy men and women. Gastroenterology 1991; 101: 977-90
52. Renwick AG, Ahsan CH, Challensor VF, et al. The influence of posture on the pharmacokinetics of orally administered nifedipine. Br J Clin Pharmacol 1992; 34: 332-6
53. Bennett CE, Herdy JG, Wilson LG. The influence of posture on gastric emptying of antacids. Int J Pharm 1984; 21: 341-7
54. Timmermans J, Andre JM. Factors controlling the buoyancy and gastric retention capabilities of floating matrix capsules: new data for reconsidering the controversy. J Pharm Sci 1994; 83: 18-24
55. Timmermans J, Moes AJ. How well do floating dosage forms float? Int J Pharm 1990; 62 (3): 207-16
56. Peppas NA, Bures P, Leobandung W, et al. Hydrogels in pharmaceutical formulations. Eur J Pharm Sci 2000; 50: 27-46
57. Steingoetter A, Kunz P, Weishaupt D, et al. Analysis of the meal dependent intragastric performance of a gastric-retentive tablet assessed by magnetic resonance imaging. Aliment Pharmacol Ther 2003; 18 (7): 713-20
58. Fell JT, Whitehead L, Collett JH. Prolonged gastric retention using floating dosage forms. PharmTech 2000; 24 (3): 90
59. Riner JL, Byford RL, Stratton LG, et al. Influence of density and location on degradation of sustained-release boluses given to cattle. Am J Vet Res 1982; 43 (11): 2028-30
60. Clarke GM, Newton JM, Short MB. Comparative gastrointestinal transit of pellet systems of varying density. Int J Pharm 1995; 114 (1): 1-11
61. Riner JL, Byford RL, Stratton LG, et al. Influence of density and location on degradation of sustained-release boluses given to cattle. Am J Vet Res 1982; 43 (11): 2028-30
62. Lehr C M. Hass J. Developments in the area of bioadhesive drug delivery systems. Expert Opin Biol Ther 2002; 2: 287-98
63. Ponchel G, Irache JM. Specific and non-specific bioadhesive particulate systems for oral delivery to the gastrointestinal tract. Adv Drug Del Rev 1998; 34: 191-219
64. Lehr CM, Bouwstra JA, Schachat EH, et al. In vitro evaluation of mucoadhesive properties of chitosan and some other natural polymers. Int J Pharm 1992; 78: 43-8
65. Sinha VR, Singla AK, Wadhawan S, et al. Chitosan microspheres as a potential carrier for drugs. Int J Pharm 2004; 274 (1-2): 1-33
66. Park K, Robinson JR. Bioadhesive polymers as platforms for oral-controlled drug delivery: method to study bioadhesion. Int J Pharm 1984; 19 (1): 107-27
67. Haas J, Lehr CM. Developments in the area of bioadhesive drug delivery systems. Expert Opin Biol Ther 2002; 2 (3): 287-98
68. Shivakumar HG, Gowda DV, Pramodkumar TM. Floating controlled drug delivery systems for prolonged gastric residence: a review. Ind J Pharm Edu 2004; 38 (4): 172-80
69. Gupta P, Vermani K, Garg S. Hydrogels: from controlled release to pH-responsive drug delivery. Drug Discov Today 2002; 7 Suppl. 10: 569-79
70. Klausner EA, Lavy E, Friedman M, et al. Expandable gastroretentive dosage forms. J Control Rel 2003; 90: 143-62
71. Gupta P, Vermani K, Garg S. Hydrogels: from controlled release to pH-responsive drug delivery. Drug Discov Today 2002; 7 (10): 569-79
72. Moes AJ. gastric retention systems for oral drug delivery. Business Briefing 2003; 157-159 [online]. Available from URL: http://www.bbriefings.com/ [Accessed 2005 Jun 13]
73. Garg S, Sharma S. Gastroretentive drug delivery systems. Business Briefing 2003; 160-66 [online]. Available from URL: http://www.bbriefings.com/ [Accessed 2005 Jun 13]
74. Atyabi F, Sharma HL, Sharma H, et al. Controlled drug release from coated floating ion exchange resin beads. J Control Rel 1996; 42 (1): 25-8
75. Atyabi F, Sharma HL, Mohammad HAH, et al. In vivo evaluation of a novel gastric retentive formulation based on ion exchange resins. J Control Rel 1996; 42 (2): 105-13
76. Burton S, Washington N, Steele RJC. Intragastric distribution of ion-exchange resins: a drug delivery system for the topical treatment of the gastric mucosa. J Pharm Pharmacol 1995; 47: 901-6
77. Umamaheshwari RB, Jain S, Jain NK. A new approach in gastroretentive drug delivery system using cholestyramine. Drug Deliv 2003; 10 (3): 151-60
78. Fabregas JL, Claramunt J, Cucala J, et al. In vitro testing of an antacid formulation with prolonged gastric residence time (Almagate Flot-Coat). Drug Dev Ind Pharm 1994; (20): 1199-212
79. Washington N, Greaves JL, Wilson CG. Effect of time of dosing relative to a meal on the raft formation anti-reflux agent. J Pharm Pharmacol 1990; 42: 50-3
80. Chen J, Blevins WE, Park H, et al. Gastric retention properties of superporous hydrogel composites. J Control Rel 2000; 64: 39-51
81. Chen J, Park K. Synthesis and characterization of superporous hydrogel composites. J Control Rel 2000; 65 (1-2): 73-82
82. Park K. Superporous hydrogels for pharmaceutical and other applications. Drug Del Tech [online]. Available from URL: http://www.drugdeliverytech.com/cgi- bin/articles.cgi?.idArticle=60 [Accessed 2006 Mar 20]
83. Groning R, Werner M, Berntgen M, et al. Peroral controlled release dosage forms with internal magnets and extracorporeal magnetic guidance-investigations into the renal elimination of riboflavin. Eur J Pharm Biopharmacol 1996; 42: 25-8
84. Fujimori J, Machida Y, Tanaka S, et al. Effect of magnetically controlled gastric residence of sustained release tablets on bioavailability of acetaminophen. Int J Pharm 1995; 119: 47-55
85. Dong C, Rogers JA. Polymer-coated liposomes: stability and release of ASA from carboxymethyl chitin coated liposomes. J Control Rel 1991; 17: 217-24
86. Aamelu S, Rao KP. Studies on the carboxymethyl chitosan containing liposomes for their stability and controlled release of dapson. J Microencaps 1991; 8: 505-15
87. Takeuchi H, Yamamoto H, Niwa T, et al. Mucoadhesion of polymer-coated liposomes to rat intestine in vitro. Chem Pharm Bull 1994; 42: 1954-6
88. Arnold SC, Ferritto MS, Lenz RW, et al. pH dependent modification of phospholipid vesicle membrane by poly (carboxylic acid) bearing pendant cholesteryl esters. Polym Prepr 1986; 27: 42-3
89. Whitehead L, Fell JT, Collett JH, et al. Floating dosage forms: an in vivo study demonstrating prolonged gastric retention. J Control Rel 1998; 55 (1): 3-12
90. Patil JM, Hirlekar RS, Gide PS, et al. Trends in floating drug delivery systems. J Sci Ind Res 2006 Jan; 65: 11-21
91. Swarbrick J, Boylon JC. Encyclopedia of pharmaceutical technology. 2nd ed. Book 2. New York: Marcel Dekker, 2002: 1783-92
92. Hasim H, Li WPA. Improving the release characteristics of water-soluble drugs from hydrophilic sustained release matrices by in situ gas generation. Int J Pharm 1987; 35: 201-6
93. Chien YW. Controlled and modulated release drug delivery systems. In: Swarbrick J, Boylan JC, editors. Encyclopedia of pharmaceutical technology. New York: Marcel Dekker, 1990: 280-313
94. Krogel I, Bodmeier R. Floating or pulsatile drug delivery systems based on coated effervescent cores. Int J Pharm 1999; 187 (2): 175-84
95. Chen GL, Hao WH. In vitro performance of floating sustained release capsule of verapamil. Drug Dev Ind Pharm 1998; 24: 1067-72
96. Erni W, Held K. The hydrodynamically balanced system: a novel principle of controlled drug release. Eur Neurol 1987; 27 Suppl. 1: 21-7
97. Sheth PR, Tossounian J. The hydrodynamically balanced system: a novel drug delivery system for oral use. Drug Dev. Ind. Pharm. 1984; 10 Suppl. 2: 313-39
98. Gerogiannis VS, Rekkas DM, Dallas PP, et al. Floating and swelling characteristics of various excipients used in controlled release technology. Drug Dev Ind Pharm 1993; 19: 1061-81
99. Streubel A, Siepmann J, Bodmeier R, et al. Floating microparticles based on low density foam powder. Int J Pharm 2002; 241 (2): 279-92
100. Streubel A, Siepmann J, Bodmeier R. Floating matrix tablets based on low density foam powder: effects of formulation and processing parameters on drug release. Eur J Pharm Sci 2003; 18 (1): 37-45
101. Sato Y, Kawashima Y, Takeuchi H, et al. In vitro and in vivo evaluation of riboflavin-containing microballoons for a floating controlled drug delivery systems in healthy humans. Int J Pharm 2004; 275: 97-107
102. Sriamornsak P, Thirawong N, Puttipipatkhachorn S. Emulgel gel beads of calcium pectinate capable of floating on the gastric fluid: effect of some additives, hardening agent or coating on release behavior of metronidazole. Eur J Pharm Sci 2005; 24: 363-73
103. Samuel B, Philip A, Pathak K, et al. Preparation and evaluation of gastroretentive delivery system of flurbiprofen. Ind Pharm 2006; 45 (5): 77-9
104. Kawashima Y, Niwa T, Takeuchi H, et al. Hollow microspheres for use as a floating controlled drug delivery system in the stomach. J Pharm Sci 1992, 40
105. Jain SK, Jain NK, Agarwal GP. Floating delivery system, Gastroretentive floating drug delivery: an overview [online]. Drug Del Tech 2005 Jul/Aug; 5 (7). Available from URL: http://www.drugdeliverytech.com/cgi-bin/articles.cgi?. idArticle=400 [Accessed 2006 Jan 20]
106. Moes AJ. Gastroretentive dosage forms. Crit Rev Ther Drug Del Syst 1993; 10: 143-95
107. Timmermans J, Moes AJ. Measuring the resulting weight of an immersed test material: II. Examples of kinetic determinations applied for monolithic dosage forms. Acta Pharm Technol 1990; 36 (1): 176-80
108. Jain NK, Awasthi AM, Jain NK, et al. Calcium silicate based microspheres of repaglinide for gastroretentive floating drug delivery: preparation and in vitro characterization. J Control Rel 2005; 107: 300-9
109. Ponchel G, Irache JM. Specific and non-specific bioadhesive particulate systems for oral delivery to the gastrointestinal tract. Adv Drug Del Rev 1998; 34: 191-219
110. Park K, Robinson JR. Bioadhesive polymers as platforms for oral controlled drug delivery: method to study bioadhesion. Int J Pharm 1984; 19 (2): 107-27
111. Peppas NA, Little MD, Yanbin H. Bioadhesive controlled release system. In: Wise DL, editor. Handbook of pharmaceutical controlled release technology. New York: Marcel Dekker, 2000: 255-70
112. Liu Z, Lu W, Qian L, et al. In vitro and in vivo studies on mucoadhesive microspheres of amoxicillin. J Control Rel 2005; 102 (1): 135-44
113. Klausner EA, Lavy E, Stepensky D, et al. Novel gastroretentive dosage forms: evaluation of gastroretentivity and its effect on riboflavin absorption in dogs. Pharm Res 2002; 19: 1516-23
114. Groning R, Berntgen M, Georgarakis M. Acyclovir serum concentrations following peroral administration of magnetic depot tablets and the influence of extracorporal magnets to control gastrointestinal transit. Eur J Pharm Biopharm 1998; 46: 285-91
115. Pham AT, Lee PI. Probing the mechanism of drug release from hydroxy propylmethyl cellulose metrics. Pharm Res 1994; 11: 1379-84
116. Klausner EA, Lavy E, Friedman M, et al. Expandable gastroretentive dosage forms. J Control Rel 2003; 90: 143-62
117. Hilton AK, Deasy PB. In vitro and in vivo evaluation of an oral sustained-release floating dosage form of amoxycillin trihydrate. Int J Pharm 1992; 86 Suppl. 1: 79-88
118. Ronge N, Cole ET, Doelker E, et al. Buoyancy and drug release patterns of floating minitablets containing piretanide and atenolol as model drugs. Pharm Dev Technol 1998; 3 (1): 73-84
119. Pillay V, Fassihi R. Evaluation and comparison of dissolution data derived from different modified release dosage forms: an alternative method. J Control Rel 1998; 55 1: 45-55
120. Burns SJ, Attwood D, Barnwell SG. Assessment of the dissolution vessel designed for use with floating and erodible dosage form. Int J Pharm 1998; 160 (2): 213-8
121. British pharmacopoeia 1993. London: HMSO, 1993
122. Harland RS, Gazzaniga A, Sangalli ME, et al. Drug/polymer matrix swelling and dissolution. Pharm Res 1988; 5: 488-94
123. Xiaoquiang X, Minjie S, Feng Z, et al. Floating matrix dosage form for phenoporlamine hydrochloride based on gas forming agent: in vitro and in vivo evaluation in healthy volunteers. Int J Pharm 2006; 310: 139-45
124. Yang LB, Fassihi RA. Zero-order release kinetics from a self-correcting floatable asymmetric configuration drug delivery system. J Pharm Sci 1996; 85: 170-3
125. Sangekar S, Vadino WA, Chaudry I, et al. Evaluation of the effect of food and specific gravity of tablets on gastric retention time. Int J Pharm 1987; 35: 187-91
126. Joseph NJ, Lakshmi S, Jayakrishnan A. A floating-type oral dosage form for piroxicam based on hollow polycarbonate microspheres: in vitro and in vivo evaluation in rabbits. J Control Rel 2002; 79: 71-9
127. Chavanpatil M, Jain P, Chaudhari S, et al. Development of sustained release gastroretentive drug delivery system for ofloxacin: in vitro and in vivo evaluation. Int J Pharm 2005; 304: 178-84
128. Mojaverian I, Chan K, Desai A. Gastrointestinal transit of a solid indigestible capsule as measured by radiotelemetry and dual gamma scintigraphy. Pharm Res 1989; 6: 719-24
129. Fell JT, Digenis GA. Imaging and behaviour of solid oral dosage forms in vivo. Int J Pharm 1984; 22 (1): 1-15
130. Ingani HM, Timmermans J, Moes AJ. Conception and in vivo investigation of peroral sustained release floating dosage forms with enhanced gastrointestinal transit. Int J Pharm 1987; 35: 157-64
131. Philip AK, Pathak K. Osmotic flow through asymmetric membrane: a means for controlled delivery of drugs with varying solubility [online]. AAPS PharmSciTech 2006 Jul 7; Suppl. 3: Article 56. Available from URL: http://www.aap-spharmscitech.org/view.asp?art=pt070356 [Accessed 2006 July 8]
132. Gupta SK. Stability studies of ampicillin floating tablets (Ampiflot) and buffered ampiflot [masters thesis]. New York: St John's University, 1987
133. Kulkarni GT, Gowthamarajan K, Suresh B. Stability testing of pharmaceutical products: an overview. Ind J Pharm Edu Res 2004; 38 (4): 194-202
134. Stability testing guidelines: stability testing of new drug substances and products [online]. Available from URL: http://www.emea.eu.int [Accessed 2005 Jul 8]
135. O'Laughlin JC, Hoffiezer JW, Ivery KJ. Effect of aspirin on the stomach in normals: endoscopic comparison of damage produced one hour, 24 hours and 2 weeks after administration. Scand J Gastroenterol 1981; 16 Suppl. 67: 211-4