Drug Delivery Systems for Treatment of Systemic Hypertension

Abstract

Novel drug delivery systems are available in many areas of medicine. Their application in the treatment of hypertension continues to widen. Oral drug delivery systems permit antihypertensive agents that were previously administered two to four times daily to be administered once daily. Biotechnical use of chemical-dispensing systems has been applied to propranolol (polymer coated beads), clonidine (transdermal therapeutic system), nifedipine (osmotic pump and coat-core), isradipine (osmotic pump), verapamil (sodium alginate and spheroidal oral delivery absorption system), felodipine (coat-core), nisoldipine (coat-core) and diltiazem (polymer coated beads and Geomatrix. The initial goal was to lower blood pressure by a uniform amount throughout the entire day. Now, new drug delivery systems are being developed to target blood pressure in the early morning hours when most cardiovascular events occur. Two chronotherapeutic drug delivery systems are now available for verapamil (chronotherapeutic oral delivery absorption system and delayed coat osmotic pump). Disadvantages of sustained-release products include delayed achievement of pharmacodynamic effect, unpredictable bioavailability, enhanced first-pass hepatic metabolism, dose dumping, sustained toxicity, dosage inflexibility and increased cost. Potential advantages include reduced administration frequency, enhanced adherence and convenience, reduced toxicity, stable drug concentrations, uniform drug effect, decreased cost (occasionally) and decreased daily dosage.

Oral pulsatile delivery: Rationale and chronopharmaceutical formulations

“…Osmotic pumping was relied on to develop a once-a-day controlled-onset extended-release (COER-24) formulation of verapamil hydrochloride (Gupta et al, 1996;Prisant and Elliott, 2003). In accordance with the OROS ® Push-Pull TM technology, COER-24 consisted of a bipartite core tablet including an expanding polymeric compartment and a drug compartment.…”

Artificial Organs: A New Option for Treating Osteoarthritis

“…In the most common form, the oral dosage form, it consists of a core containing a medicine covered with a thin semi-permeable diaphragm. Oral osmotic systems now address diverse areas with more than a dozen products marketed worldwide [42]. Depending on the difference in the osmotic pressure within the core and the fluid outside layer, it comes to a constant and continuous emission of the active agent.…”

Quantification of isradipine in human plasma using LC–MS/MS for pharmacokinetic and bioequivalence study

“…Isradipine (methyl propan-2-yl 2,6-dimethyl-4-(8-oxa-7,9 diazabicyclo [4.3.0] nona-2,4,6,9-tetraen-5-yl)-1,4-dihydropyridine-3,5-dicarboxylate) belongs to the dihydropyridine class of calciumchannel blockers and is commonly used to treat hypertension associated with various clinical conditions [1][2][3][4][5][6]. Isradipine acts by inhibiting the influx of extracellular calcium across both the cardiac and vascular cell membranes and has a high affinity for L-type channels located in vascular smooth muscle compared to those in the myocardium, thereby leading to a fairly specific and potent antihypertensive effect [7,8].…”