in recent years, great efforts have been devoted to the design of drug delivery systems. many polymeric excipients have been studied in order to make drug release fit the desired profiles. the aim of this work was to design a theophylline oral suspension, as sustained release pharmaceutical preparation in order to decrease the plasma level fluctuations and adverse effects of theophylline. micro...

used in the treatment of asthma, chronic obstructive pulmonary disease and apnoea (1, 2). Because of the narrow therapeutic index of theophylline, therapeutic drug monitoring is indicated for safe and effective treatment (3). Clinical manifestations of theophylline toxicity include nausea, vomiting, hypokalaemia, hyperglycaemia, metabolic acidosis, tachycardia, cardiac arrhythmias, and seizures...

A survey was conducted to investigate the medication taken by asthmatics presenting to a casualty department, particularly with reference to theophylline. Serum levels of theophylline were measured to give an indication of the effectiveness of the therapy. Most patients were found to be taking some form of theophylline regularly, and serum levels measured were in the therapeutic range. Under-do...

Serum theophylline levels were measured throughout the day in 65 asthmatic children receiving one of two slow-release theophylline compounds. There was a wide interindividual variation in levels obtained with similar doses of pure theophylline, and also a wide intraindividaual variation in levels throughout the day, suggesting that the rates of release and/or absorption of theophylline from the...

The xanthan/chondroitin sulfate (X/CS) hydrogels, obtained by a crosslinking technique, were evaluated in vitro and in vivo as matrices for theophylline release. The influence of pH of simulated physiological media on the X/CS swelling behaviour at 37 ̊C was investigated. The hydrogels theophylline loading degree was evaluated by near infrared chemical imaging (NIR-CI) technique and confirmed al...

Organic anion transporter 2 (Oat2 [SLC22A7]) is a multispecific organic anion transporter. Although several substrates of human Oat2 (hOat2) have been elucidated, a possible involvement of hOat2 in drug interaction is less defined. The purpose of this study was to investigate the interaction of theophylline with erythromycin mediated by hOat2 using a Xenopus laevis oocyte expression system. Whe...

Seizures is a major toxicity of theophylline. The mechanism of theophylline-induced seizures is not known, but antagonism at adenosine receptors may be a possibility. The effect of pretreatment with different doses of adenosine (100, 500 and 1000 mg/kg, i.p.), and the adenosine A1 receptor agonist N6-cyclopentyladenosine (CPA), 1, 5 and 10 mg/kg, i.p., was studied against seizures induced by th...

In the driven isolated left atrium of the rabbit theophylline shortened relaxation time in a similar manner to isoprenaline and histamine. 2 Phenylephrine lengthened relaxation time in a similar manner to calcium. 3 Theophylline caused phenylephrine to shorten relaxation time, which was inhibited by a beta-adrenoceptor blocking drug, but theophylline did not potentiate the effect of phenylephri...

BACKGROUND While cytochrome P4501A2 is the primary pathway for theophylline (aminophylline ethylenediamine) metabolism in adults, it is developmentally immature in the newborn. OBJECTIVE To report the developmental differences in theophylline toxicokinetics of neonates. DESIGN Case series. Three premature neonates received inadvertent intravenous overdoses of theophylline for apnea of prema...

We demonstrated the effect of hypoalbuminemia on theophylline disposition in rats. The pharmacokinetic parameters in Sprague-Dawley rats (SDRs) were compared with those in spontaneously hyperlipidemic rats (HLRs), which had approximately one half the serum albumin concentration of the SDRs, after a single 10 mg/kg injection (iv) of theophylline. Theophylline clearance (CL) in the HLRs was incre...