Systemic routes, administration

The other main route used for pharmaceutical preparations is inhalation using a head only exposure system. Parenteral administration, although technically possible, is usually avoided because of the local irritant effects that can occur with repeated injection, particularly by the subcutaneous route. Topical administration is an option for materials intended for administration to the skin. 

Intracoronary, intravenous, or sublingual nitrate administration consistently increases the caliber of the large epicardial coronary arteries except where blocked by concentric atheromas. Coronary arteriolar resistance tends to decrease, though to a lesser extent. However, nitrates administered by the usual systemic routes may decrease overall coronary blood flow (and myocardial oxygen consumption) if cardiac output is reduced due to decreased venous return. The reduction in oxygen consumption is the major mechanism for the relief of effort angina. 

On initial inspection, the skin is an unlikely route for systemic drug administration. Evolution has provided the mammalian organism with an external covering, the principal function of which is to act as a barrier, specifically to the loss of tissue water. Think about it the concentration of water inside the human body is... 

The immune responses to VB4-845 by both the intended local route and systemic route of administration were investigated. Not surprisingly, a dose-dependent anti-drug antibody response was observed to both the antibody and toxin portions of the construct and a similar level antibody titer was induced regardless of sex. The VB4-845 titer following local administration was significantly higher than that observed after systemic administration at the same dose level, a phenomenon that has been demonstrated to be due to the use of different routes of delivery [50],... 

Systemic steroids are also the cause of numerous negligence claims.These drugs have side effects that can result in serious injury, even death, and consequently must be used conservatively. Systemically administered drugs, with their risk of systemic complications, should not be used if a topical route of administration suffices, and practitioners must be prepared to justify the selection of a systemic route of administration when complications result and a topical route of administration initially was not used. Whenever systemic steroids are prescribed, practitioners must warn patients of side effects, monitor patients adequately so that preventable injuries can be detected, and document the care rendered. 

Over the last 20 years, transdermal route of delivery has been considered as a means for systemic drug administration. Over this period, sonophoresis has been attempted to enhance systemic transdermal delivery. Levy et al. ° showed that 3-5 min of ultrasound exposure (IMHz, 1.5W/cm ) increased transdermal permeation of mannitol and physostigmine across hairless rat skin in vivo by up to 15-fold. They also reported that the lag time typically associated with transdermal drug delivery was nearly-completely eliminated after exposure to ultrasound. ° ... 

It can never be emphasized enough that the eyes are a potential route for systemic drug administration. This has been illustrated by a British case of pulmonary edema in a child, apparently attributable to systemic absorption of phenylephrine eye-drops (1). 

Chronic treatment with the enzyme inducer phenobarbital enhances the biliary excretion of drug molecules and their metabolites by increasing liver size, bile flow, and more efficient transport into the bile. This behavior is not shared by all inducers of the CYP450 monooxygenases. The route of administration also may influence excretion pathways. Direct administration into the portal circulation might be expected to result in more biliary excretion than could be expected via the systemic route. 

Other routes of administration arc theoretically possible such as rectal route (rectal capsules and rectal suppositories) for drugs having systemic effects such a.s sedatives, tranquilizers, and analgesics topical route (patchs) for drug absorption (hormones or nicotine) into the systemic circulation parenteral route (administration of parenteral suspensions or implantation of compressed pellets). 

Membranes play a fundamental role also in the colon-specific drug delivery systems. This administration route, whose advantages have been well recognized and documented [158], provides more effective therapy of colon-related diseases such as irritable bowel syndrome and inflammatory bowel disease (IBD) including Crohn s disease and ulcerative colitis. 

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