Drug administration intra-articular

Parenteral drug administration means the giving of a drug by the subcutaneous (SC), intramuscular (IM), intravenous (IV), or intradermal route (Fig. 2-5). Other routes of parenteral administration that may be used by the primary care provider are intralesional (into a lesion), intra-arterial (into an artery), intracardiac (into the heart), and intra-articular (into a joint), hi some instances, intra-arterial dragp are administered by a nurse. However, administration is not by direct arterial injection but by means of a catheter that has been placed in an artery. 

The primary care provider may administer a drug by the intracardial, intralesional, intra-arterial, or intra-articular routes. The nurse may be responsible for preparing the drug for administration. The nurse should ask the primary care provider what special materials will be required for administration. 

The IM and SC routes are by far the most frequently used extravascular parenteral routes of drug administration in farm animals. The less frequently used parenteral routes have limited application, in that they aim at directly placing high concentrations of antimicrobial agent close to the site of infection. These routes of administration include intra-articular or subconjuctival injection and intra-mammary or intra-uterine infusion. These local routes differ from the major parenteral routes in that absorption into the systemic circulation is not a prerequisite for delivery of drug to the site of action. The combined use of systemic and local delivery of drug to the site of infection represents the optimum approach to... 

Some pharmacokinetic properties of the commonly used amide local anesthetics are summarized in Table 26-2. The pharmacokinetics of the ester-based local anesthetics have not been extensively studied owing to their rapid breakdown in plasma (elimination half-life < 1 minute). Local anesthetics are usually administered by injection into dermis and soft tissues around nerves. Thus, absorption and distribution are not as important in controlling the onset of effect as in determining the rate of offset of local analgesia and the likelihood of CNS and cardiac toxicity. Topical application of local anesthetics (eg, transmucosal or transdermal) requires drug diffusion for both onset and offset of anesthetic effect. However, intracavitary (eg, intra-articular, intraperitoneal) administration is associated with a more rapid onset and shorter duration of local anesthetic effect. 

Substantial progress has also been reported with regard to the synthesis and testing of nuclease-resistant ribozyme drugs. Modifications including phosphorothioates and nucleoside analogs have been demonstrated to be incorporable in many sites in hammerhead ribozymes, to increase nuclease resistance and support retained ribozyme activity (59-61). In fact, modified relatively nuclease-resistant ribozymes were reported to decrease the target, stromelysin, mRNA levels in knee joints of rabbits after intra-articular injection (62). Further, the pharmacokinetics of a relatively nuclease-stable hammerhead ribozyme were determined after intravenous (i.v.), subcutaneous (s.c.), or intraperitoneal (i.p.) administration to mice. The ribozyme... 

The route of administration depends on the disease being treated and the physicochemical, pharmacologic, and pharmacokinetic properties of the drug (Table 33.1). The clinically available adrenocorticoids may be administered by IV injection, oral tablets or solutions, topical formulations, intra-articular administration, and oral or nasal inhalation (Table 33.2). Only a handful of... 

Cortisone acetate or hydrocortisone usually is the corticosteroid of choice for replacement therapy in patients with adrenocortical insufficiency, because these drugs have both glucocorticoid and mineralocorticoid properties. Following oral administration, cortisone acetate and hydrocortisone acetate are completely and rapidly deacetylated by first-pass metabolism (37). Much of the oral cortisone, however, is inactivated by oxidative metabolism (Fig. 33.9) before it can be converted to hydrocortisone in the liver. The pharmacokinetics for hydrocortisone acetate is indistinguishable from that of orally administered hydrocortisone. Oral hydrocortisone is completely absorbed, with a bioavailability of greater than 95% and a half-life of 1 to 2 hours (23). The metabolism of hydrocortisone (Fig. 33.9) has been previously described. Cortisone acetate is slowly absorbed from IM injection sites over a period of 24 to 48 hours and is reserved for patients who are unable to take the drug orally. The acetate ester derivative demonstrates increased stability and has a longer duration of action when administered by IM injection. Thus, smaller doses can be used. Similarly, hydrocortisone may be dispensed as its 21-acetate (hydrocortisone acetate), which is superior to cortisone acetate when injected intra-articularly. Systemic absorption of hydrocortisone acetate from intra-articular injection sites usually is complete within 24 to 48 hours. When administered intrarectally, hydrocortisone is poorly absorbed (38,39). 

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