CAPTOPRIL is an angiotension-converting enzyme inhibitor used in the treatment of hypertension. It is freellly water soluble and has an elimination half-life after oral dose of 1.7 h. Various methods are available to formulate water soluble drugs into sustained release dosage forms by retarding the dissolution rate. One of the methods used to control drug release and hence, prologn therapeutic activity is to use hydrophilic and lipophilic polymers. In this study the effects of various polymers (hydroxyprpylemethylcellulose,) ethyl cellulose and sodium carboxymethylcellulose) and surfactants (sodium lauryl sulphate, ceytltriammonium bromide and arlacel 60) on the release rate of CAPTOPRIL were investigated. The results showed that an increase in the amount of HPMC KI5M resulted in a reduction in the release rate of CAPTOPRIL from matrices. When the HPMC was partly replaced by NaCMC (the ratio of HPMC: NaCMC was 5:1) the release rate of the drug significantly decreased. However, there was no significant difference in release rate of CAPTOPRIL from matrices PRODUCED with the ratios of 5:1 and 2:1 of HPMC:NaCMC. The presence of lactose in matrices containing HPMC and NaCMC increased the release rate of CAPTOPRIL. It was interesting that although partial replacement of HPMC by EC reduced the release rate of the drug (ratio of HPMC: EC was 2:1), when the ratio of HPMC:EC was reduced to 1:1 the release rate was increased. The effects of various surfactants on the release rate of CAPTOPRIL from HPMC: EC (1:1) matrices was also investigated. The results showed that the surfactants did not significantly change the release rate of the drug. Release rate of the drug. Release data were examined kinetically and the ideal kinetic models were estimated for the drug release.

CAPTOPRIL, an angiotensin-converting enzyme inhibitor (ACEI), has an excellent clinical effectiveness in the treatment of hypertension and congestive heart failure (CHF). Up to now various attempts have been made to make a sustained-release drug delivery system of CAPTOPRIL. One of these systems is known as "Hydrodynamically balanced system". Such a system is useful for drugs well absorbed in the proximal gastrointestinal tract or for drugs that degrade in the intestinal fluid (like CAPTOPRIL). The aim of this study was: designing, formulation and in-vitro releasing pattern evaluation of floating and bioadhesive sustained-release CAPTOPRIL matrix tablets, especially by using yellow bees wax in the formulations. Investigation of stability of CAPTOPRIL solutions with various concentrations indicated that these solutions are stable in the conditions of dissolution test (HCI 0.1 N, at 37±0.5 °c) regardless of air and light, and there is no need to add an antioxidant agent to the dissolution medium. Among different tablet formulations which were made, the formulation known as 03 (Containing: 30% yellow bees wax, 30% HPMC, 16% carbopol and 5% magnesium stearate) showed a suitable releasing pattern and a high production efficiency During dissolution tests these tablets remained floating. In the progress of this investigation it was proved that there is a direct relation between tablets hardness and granule production efficiency with P/W ratio (powders which used in granulation (P) to wax content of production (W). On the other hand it was indicated that there is a reverse relation between buoyancy time of tablets and their hardness.

Angioedema is a rare disease with autosomal dominant is largely complement system. This disease is characterized by non-itchy mucocutaneous and non-pitting edema. In some cases, this disease appears as a result of CAPTOPRIL intake which is orally and sublingually used in the treatment of severe hypertension.In this study, angioedema as a rare complication of CAPTOPRIL sublingual intake was investigated in a 49-years-old patient. In several hours after taking CAPTOPRIL, patient showed the Angioedema signs. Due to severe edema of tongue, lips and larynx, quick tracheostomy was performed and patient was hospitalized in intensive care unit. Having started the treatment measures and hospitalization, the patient discharged with good general condition.

Bartter syndrome presenting in neonatal or early infancy is characterized by salt loosing tubulopathy, hypokalemia, and metabolic alkalosis. Failure to thrive is one of the most common findings in neonatal bartter syndrome. Angiotensin converting enzyme inhibitors are one of the therapeutic options for improving growth in these patients.We describe a case of neonatal bartter syndrome with mild impairment of renal function for whom CAPTOPRIL started to promote better growth but she presented later with clinical and laboratory signs of exacerbation of renal impairment which were significantly resolved after discontinuing CAPTOPRIL.In patients with Bartter syndrome and underlying renal dysfunction angiotensin converting enzyme inhibitors should be used with caution and low dose.

A new series of alkylthio imidazole analogues of CAPTOPRIL, an ACE inhibitor used in the treatment of hypertension, was designed and synthesized in order to obtain agents more active than CAPTOPRIL with less side effects. All the compounds thus prepared were purified and characterized by IR, NMR and Mass analytical instruments.

Objective(s): Electrospun nanofibrous mats of Polycaprolactone (PCL) and amino modified SBA-15 containing CAPTOPRIL were prepared and release of drug from prepared nanofibers were investigated in this study. Materials and Methods: Amino modified SBA-15 synthesized through grafting with aminopropyl triethoxy silane. Then, CAPTOPRIL which is used as an Angiotensin-Converting Enzyme (ACE) inhibitor was loaded as a model drug into the synthesized particles. Furthermore, silica particles containing different amounts of CAPTOPRIL (7. 5, 10, 15 mg) were loaded into PCL nanofibers’ structure using electrospinning. Therefore, CAPTOPRIL’s release rate in phosphate buffer was analyzed. The analysis of CAPTOPRIL-loaded silica and CAPTOPRIL-loaded nanofibers (without silica) was done in vitro matrix. To identify the acquired nanofibers, FTIR, SEM, SEM mapping, EDX and average diameter calculation were performed. Results: Comparison between the drug release rate of silica-containing nanofibers and bare silica particles indicated that silica particles positively affected the drug release rate. Moreover, kinetic studies have revealed that the drug release rate follows Higuchi and Korsmeyer-Peppas model. Bare nanofibers’ average diameter was 209 nm while silica and CAPTOPRIL containing nanofibers were 286 nm in average diameter. Conclusion: Therefore, it was concluded that drug-loaded Polycaprolactone nanofibers are potential candidates for biomedical applications.