Controlled Release Salbutamol Research Articles

Controlled release salbutamol sulphate microcapsules prepared by emulsion solvent-evaporation technique and study on the release affected parameters

Microcapsules of salbutamol sulphate with ethylcellulose were prepared using an emulsion-solvent evaporation technique and by the use of two different stirrer types, propeller and magnet. Different amounts of drug were added in order to obtain various drug to polymer ratios. The physical properties, loading efficiency and dissolution rate depended on the emulsion-solvent evaporation technique and on the drug to polymer ratio. Tween 80 was used as a dispersing agent. For a given drug to polymer ratio the percentage amount of Tween 80 affected the release of salbutamol sulphate and the size distribution of microcapsules. In order to further investigate the type of drug release mechanism taking place, the dissolution data were plotted according to the four different kinetic models. In vitro dissolution studies showed that first-order and square-root of time (Higuchi model) release characteristics were exhibited.

The effect of salbutamol controlled release on bronchial hyperresponsiveness in patients with bronchial asthma

Bronchial provocation test is a ,neasure oftracheobronchial sensitivity, where the increasing degree of bronchial hyperresponsiveness corresponds to the severity of the astfunatic attack. The uethod of Cockroft is used to ,neasure the serxitivity of the respiratory tract, and the nost frequently used paranteter is PCzo, which Drcasures the inhalation dose causittg a 2O% decrease in the expiration volutne afler the first second (FEVu. The ain of this study is to investigate the effect of controlled release salbutamol on bronchial hyperresponsiveness. Twenty adult asthtnatic patients were provocated by the inhalation of ntetacholine solution and their bronchial hyperresponsiveness were neasured to get the PCzo and PDzo values. Measurenents were conducted 5 tines, 2 times at the run in period, once at the 2nd and 4th week oftreatment, and once at the 2nd week ofier trearnent. The result of this study showed an increase itt PC2s itt patients treated by 4 ng and 8 ng controlled release salbutanol (1.24 + 1.51 and 1.38 + 1.65 at the ntn in period, were increasedto 1.30+ 1.18and 1.81 + L62atthe2ndweekof teatutent,andto 1.88+ l.58and 1.49+ 1.71 atthe4thweekoftreatment respectively). Two weeks after the treatnent was stopped, the PCzovalues ofboth treatnent groups reere decreased to 1.33 + 1.26 and 1.29+ I.2l.TheseincreaseanddecreaseinPCzovaLueswereslatisticallynotsignificant,soweconcludedthata4weeksadrninistration ofcontrolled release solbutauol astfunatic patient is not effective in reducing bronchial hyperrespon-siveness.

The safety and tolerability of the β2‐agonist salbutamol in an event monitoring study of an oral controlled release formulation (‘Volmax’)

AbstractObjective — The original study objective was to assess the safety and tolerability of a controlled release formulation of salbutamol (‘Volmax®’), with particular regard to side‐effects related to the delivery system. As the study progressed, an opportunity to review the tolerability of oral administration of salbutamol became apparent.Design — An observational cohort event monitoring study of patients requiring bronchodilator therapy who were prescribed controlled release salbutamol (Volmax) for the first time. A comparator group of patients prescribed any other orally administered bronchodilator for the first time was included. Patients were monitored for a minimum of six months to a maximum of 24 months.Setting — General Practice in the United Kingdom.Main outcome measures — All clinical events during the observation period were recorded. In the analysis particular attention was paid to those events which might be associated with ‘dumping’ of the active ingredient, an excess of gastrointestinal side‐effects, cardiovascular and respiratory morbidity or mortality.Results — A total of 8731 patients were studied; 7750 on Volmax and 981 on comparators. The comparator group comprised 622 patients receiving xanthines, 346 receiving oral beta2‐agonists other than Volmax, and 13 other patients taking a variety of medications such as ephedrine‐based products. There was no significant difference in mortality rates within 24 months of registration which were 5.5% (95% confidence limits 5.0–6.0%) in the Volmax group and 5.6% (4.16–7.03%) in the comparators. There was no evidence that salbutamol in the controlled delivery system studied produced significant gastrointestinal symptoms or any safety problems. The incidence of dyspepsia, heartburn, nausea and vomiting was higher in the xanthine group at 15.3% (12.48–18.12%) than in the Volmax group or in the beta2‐comparators which had incidences of 5.5% (5.0–6.0%) and 4.6% (2.39–6.80%) respectively.The incidences of tremor and cramp was higher in patients treated with Volmax than in those receiving other beta2‐agonists or xanthines; 12.78% (12.05–13.50%), 5.78% (3.33–8.23%) and 3.37 (1.95–4.78%), respectively. More patients in the Volmax group had experienced previous intolerance to salbutamol than in both the comparator sub‐groups. The incidence of diarrhoea in patients receiving Volmax was 3.07% (2.68–3.45%), in those receiving other beta2‐agonists 2.31% (0.72–3.89%) and in those treated with xanthines 1.13% (0.30–1.96%). Although the incidence of diarrhoea was slightly higher in patients receiving Volmax or other beta2‐agonists than in those receiving xanthines, it did not result in discontinuation of therapy.Conclusion — This study provides extensive safety data on the use of a controlled release formulation of salbutamol in general practice. The methodology used was sensitive enough to detect a previous unrecognized minor side‐effect of oral β2‐agonist treatment, and showed no clinically significant safety problems associated with the OROS delivery system or salbutamol itself.

Effect of controlled-release salbutamol in predominantly non-reversible chronic airflow obstruction

We conducted a multicentre, randomized, double-blind, placebo-controlled, parallel group study to determine the efficacy of controlled release salbutamol (SCR) tablets in clinically stable patients with predominantly non-reversible chronic airflow obstruction (CAO). Patients received either 8 mg SCR or matching placebo tablets twice daily for 6 weeks. Fifty-eight patients (30 on SCR and 28 on placebo) completed the study. Outcome measurements included FEV1, FVC, 6-min walking distance, and patient assessment of efficacy recorded at the clinic visits and twice daily PEFR measurements plus daytime symptom score recorded in diary cards. The absolute change between baseline and 6-week measurements with SCR was compared to that with placebo. Favourable trends were observed with SCR for all variables tested except FVC. The only significant difference between SCR and placebo was in FEV1 where there was a small net change of 95 ml in favour of SCR. We conclude, therefore, that the effects of lung function of long-term bronchodilator therapy with SCR in patients with stable non-reversible CAO are slight, and are likely to be of limited clinical benefit.

Effect of controlled release salbutamol on nocturnal cough in asthma.

Sixteen asthmatic children completed a double blind placebo controlled crossover study of controlled release salbutamol (CRS) to assess its efficacy in controlling night time cough. Children with asthma were enrolled into the study on the basis of a history of persistent cough confirmed by two overnight tape recordings at home. Outcome was measured by two overnight tapes on each medication. Other treatment was unaffected. There was no significant fall in cough counts on CRS. Median scores were 14.5 and 12.0 coughing episodes per night for CRS and placebo respectively. Mean overnight oxygen saturation was identical in both treatment periods but morning peak flow showed a trend towards improvement on CRS. Treatment with CRS does not have a significant effect in control of night cough although it may improve objective measurements of lung function.

Oral controlled release salbutamol may have a place in childhood asthma

Oral controlled release salbutamol may have a place in childhood asthma

Controlled - release salbutamol tablets

Controlled-release salbutamol tablets (Volmax - Ventolin CR) have superseded the now obsolete Ventolin Spandets. This new preparation, marketed as two brands by subsidiaries of Glaxo in pseudo-competition, is a sustained-release formulation designed to provide smooth release of salbutamol over 12 hours allowing twice daily dosage. The manufacturers list as indications “all forms of reversible airflow limitation”, but most would regard inhaled β2agonists and corticosteroids as the best treatment for these conditions. Given the efficacy and safety of these inhaled drugs it is questionable what the aim of oral treatment would be. What then, is the role of controlled-release salbutamol tablets?

Controlled Release Salbutamol Sulphate Molded Tablets Using Eudragit Retard

AbstractPermeable acrylic resins were used as efficient retarding materials to prepare controlled release salbutamol sulphate molded tablets. The formulation is simple, efficient, economic and is easily shaped into molded tablets. The effects of two types of acrylic resins, namely: Eudragit RL100 ad Eudragit RS100 in concentrations 1, 2 and 5% w/w on the physical characteristics as well as on the in vitro release patterns of salbutamol sulphate from molded tablets prepared with either polyethylene glycol (PEG) 4000 or 6000 were studied. It was revealed that, as the molecular weight of the PEG increased, the hardness of the tablets increased. Considerable retardation in the drug release was observed by using Eudragit RS100 as compared to Eudragit RL100. The formulation prepared with PEG 6000 and 5% Eudragit RS100 produced much more release time prolongation than the other tested formulations. On the other hand, tablets prepared by the direct compression technique produced a faster release of salbutamol sul...