Sustained-release Theophylline Matrix Tablet Using Hydrophilic Polymers: Effects of Agitation Rates and pH on Release Kinetics

Background and Objective: Modified-release tablet of theophylline that can increase its usefulness despite narrow therapeutic index and short half-life, is being formulated. However, the rate and extent of release of a sustained-release delivery system can be affected by some factors. This work is aimed at investigating the effect of agitation rates and pH of dissolution medium on release kinetics of sustained-release theophylline tablet formulated using hydrophilic polymers. Materials and Methods: Theophylline granules was formulated using 3 polymers (HPMC, SCMC and Sodium alginate) to form 3 batches of granule by wet granulation method, using 95% ethanol. The granules compacted to batches of sustained-release matrix tablets. The tablet batches were characterized for tablet properties, and dissolution studies carried out using simulated gastric and intestinal fluid separately at different agitation rates. The data from dissolution studies were subsequently fitted into 4 drug release kinetics models. Results: The swelling of the 3 polymers over time was noteworthy, although there was no significant difference between them. The release kinetic followed the Higuchi model and zero-order releasing more than 90% over 8 hours period, with t10 and t90 released at 14 minutes and 6.8 hours respectively. The mechanical properties of the tablets were within the acceptable limit. Conclusion: The agitation rate and pH of the medium had no significant effect on the release of the theophylline from the batches of matrix tablets except in the case of F1 which showed a marginally significant effect.

Observation of the Improvement in Nocturnal Asthma Symptoms with Administration of Once Daily Sustained Released Theophylline

Objective: The aims and objective of this study to observe the improvement in Nocturnal Asthma symptoms and Quality of Life (QoL) with administration of once daily sustained release theophylline preparation.Background: Nocturnal symptoms are a common part of the asthma. Nocturnal asthma is defined by a drop in forced expiratory volume in 1 second (FEV1) of at least 15% between bedtime and awakening in patients with clinical and physiologic evidence of asthma, which may include improvement in QoL.Methodology: The patient with Chronic Persistent Asthma, both sex, age >18 to 50 years of age and preferably patients with nocturnal exacerbations were included in the study. All patients were diagnosed on the basis of clinical history, physical examination, chest X-ray and pulmonary function tests, in accordance with the clinical criteria for the diagnosis by the GINA. The recruitment period was between March 2017 and August 2017 Shaheed Suhrawardy Medical College Hospital, Dhaka.Results: It was observed that 65(92.85%) was found exacerbation free night and 5(7.15%) patients were found exacerbation with sustained release Theophylline. There are significantly improved qualities of life between 1st follow up to 2nd follow up, 3rd follow up and 4th follow up p<0.001 which was statistically significant. Spirometry test was gradually improved between 1st visit of FEV1 to 2nd, 3rd and 4th visit of FEV1, (p<0.001) that was statistically significant.Conclusion: Most of the patients were found exacerbation free night. There are significantly improved quality of life between 1st follow up to 2nd follow up, 3rd follow up and 4th follow up in Spirometry test. The value of FEV1 was gradually improve in the lst visit, 2nd, 3rd and 4th visit with sustained release Theophylline.J Shaheed Suhrawardy Med Coll, December 2017, Vol.9(2); 74-77