Routes of administration parenteral

Route of administration. Parenteral therapy (which may be i.m. or i.v.) is preferred for therapy of serious infectiorrs because high therapeutic concentrations are achieved reliably and rapidly. Initial parenteral therapy should be switched to the oral route whenever possible once the patient has improved clinically and as long as they are able to absorb the drug i.e. not with vomiting, ileus or diarrhoea. Many antibiotics are, however, well absorbed orally, and the long-held assumption that prolonged parenteral therapy is necessary for adequate therapy of serious infections (such as osteomyelitis) is often not supported by the results of clinical trials. 

Route of administration Parenteral therapy is preferred in most cases of serious microbial infections. Chlortunphenicol, the fluoroquinolones, and trimethoprim-sulfamethoxazole (TMP-SMZ) may be effective orally. 

Mechanistic studies - any study necessary to clarify effects reported in toxicity studies Studies on other routes of administration (parenteral routes)... 

Use the oral route of administration if the patient has mild nausea with minimal or no vomiting. Seek an alternative route (e.g., transdermal, rectal suppository, or parenteral) if the patient is unable to retain oral medications due to vomiting. 

Due to particle sizes in the micrometer range, parenteral suspensions are generally limited to either subcutaneous or intramuscular routes of administration. However, ultrafine suspensions can be approached by high-pressure homogenization [200]. The particle size obtained from this technique is in the 100 500 nm range, thus intravenous administration is possible [201]. General information on parenteral formulations is given in Chapter 12. 

As pharmaceutical scientists gain experience and tackle the primary challenges of developing stable parenteral formulations of proteins, the horizons continue to expand and novel delivery systems and alternative routes of administration are being sought. The interest in protein drug delivery is reflected by the wealth of literature that covers this topic [150-154]. Typically, protein therapeutics are prepared as sterile products for parenteral administration, but in the past several years, there has been increased interest in pulmonary, oral, transdermal, and controlled-release injectable formulations and many advances have been made. Some of the more promising recent developments are summarized in this section. 

Some parenteral routes of administration were less effective than others in producing an increase in the frequency of benign or malignant tumors, including intravenous, submaxillary, and intrahepatic... 

To examine the influence of different routes of administration of lipospheres on their immunogenicity, rabbits were immunized orally or parenterally (by subcutaneous, intraperitoneal, intramuscular, and intravenous routes) with lipospheres made of tristearin and lecithin (1 1 molar ratio) and containing the malaria antigen. The immune response obtained was followed with time for a period of 12 weeks postimmunization. 

No antibody activity was found after oral immunization in any of the individual rabbits immunized with liposphere R32NS 1-vaccine formulation. However, rabbit immunization by all parenteral routes tested resulted in enhanced immunogenicity, with increased antibody IgG levels over the entire postimmunization period. The individual rabbit immune response shows that immunization by subcutaneous injection was the most effective vaccination route among all parenteral routes of administration tested. 

The dosing regimens can be quite variable and at times very techniqueintensive. These chemicals are almost always administered by a parenteral route of administration normally intravenously or subcutaneously. Dosing regimens have run the range from once every two weeks for an antihormone vaccine to continuous infusion for a short-lived protein. 

There are certain clinical situations in which a parenteral route of administration is preferred to other possible routes. These include the following. 

When the amount of drug given to a subject must be precisely controlled (e.g., in many pharmacokinetic studies), it is preferable to use a parenteral (usually IV) route of administration. 

When the first-pass effect of a drug going through the liver must be avoided, a parenteral route of administration is usually chosen, although a sublingual route or dermal patch will also avoid the first-pass effect. 

Routes of administration Inhalation, direct contact with skin or eyes Oral and/or parenteral most likely... 

Nanoparticles have been studied extensively as carriers for drugs employed in a wide variety of routes of administration, including parenteral [14], ocular [15], and peroral [16] pathways. The term nanoparticle is a collective name for any colloidal carrier of submicrometer dimension and includes nanospheres, nanocapsules, and liposomes. They can all be defined as solid carriers, approximately spherical and ranging in size from 10 to 1000 nm. They are generally polymeric in nature (synthetic or natural) and can be biodegradable... 

The present chapter deals with calculations involving isotonicity, pH, and buffering of topical preparations. The discussion presented here is also relevant to the dosage forms for other routes of administration including parenteral routes. 

A nutritional deficit often exists in hospitalized patients. There are many conditions and diseases for which nutritional support is recommended by enteral or parenteral routes of administration. Provision of nutrients by vein, in amounts sufficient to maintain or achieve anabolism, is referred to as total parenteral nutrition (TPN). 

Q23 The use of a suspension as a parenteral preparation is contraindicated when the route of administration is ... 

Many studies have been carried out regarding the absorption of peptides and proteins after pulmonary drug dehvery. The perspectives of a non-parenteral route of administration for larger proteins led to studies on the pulmonary absorption of proteins of different size. To date, over 30 different proteins have been evaluated with regard to absorption rate and... 

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... 

Sporadic clinical reports, without the support of data from controlled studies, repeatedly indicate the effectiveness of intratracheal administration of parenteral antimicrobial preparations in the treatment of tracheobronchitis and pneumonia in cattle. The expectation when using this route of administration is that a greater therapeutic effect will be achieved when the drug is placed as close to the infection site as possible, rather than relying on the systemic circulation for drug delivery. 

Ideally, toxicology studies should mimic, as near as possible, human exposure. Thus, both the route of administration and the exposure should, where possible, be similar to that in man. The classic route of administration in man is oral and thus most toxicology studies are conducted by the oral route. Elowever, parenteral routes may be used either to mimic the clinical route or to ensure exposure. The administration of some medicines is directly on to highly differentiated surfaces such as the alveolar surface of the lungs or the skin. It is, therefore, important to assess the topical irritancy, absorption and subsequent systemic toxicity following such applications. It should be remembered that some compounds, for example, chlorinated hydrocarbons, may be more toxic when given by the inhalation route than when given orally or may directly affect... 

PROMETHAZINE HYDROCHLORIDE The preferred parenteral route of administration is deep IM injection properly administered IV doses are well tolerated, but this method is associated with increased hazard. IV administration should not exceed 25 mg/mL at a rate no more than 25 mg/min. Avoid subcutaneous and intra-arterial injection. Use contraindicated in patients younger than 2 years of age. 

Determine initial route of administration by the severity of symptoms. With only the earliest manifestations of diabetic gastric stasis, initiate oral administration. If symptoms are severe, begin with parenteral therapy. Administer 10 mg IV over 1 to 2 minutes. Parenteral administration up to 10 days may be required before symptoms subside, then oral administration may be instituted. Reinstitute therapy at the earliest manifestation. 

Absorption - Capreomycin sulfate is not absorbed in significant quantities from the Gl tract and must be administered parenterally. The AUC is similar for single-dose capreomycin (1 g) administered IM and by IV (over 1 hour) routes of administration. Capreomycin peak concentrations after IV infusion were approximately 30% higher than after IM administration. 

Which route of administration is optimum Choosing the optimum dmg administration route takes into account the specific circumstances of each individual case. For example, can the patient tolerate oral medications, or is intravenous administration required Does the patient have venous access For how long can it be maintained Is intramuscular administration a possibility In many clinical situations, the available formulation determines the route of administration. Antibiotics are a prime example of this phenomenon ceftriaxone, for example, is available only for parenteral administration while amoxicillin is administered orally. 

Subthreshold doses based on estimates from animal potency studies were used In the first few subjects. For example, the earliest exposures to BZ, one of the anticholinergic test compounds, were at doses between 0.1 and 0.5 ug/kg, which was less than one-tenth the incapacitating dose (ID) ultimately established at approximately 5.5 Ug/kg. The Intravenous route was preferred initially, but other routes of administration were also used. Inhalation studies were sometimes undertaken after a compound had been thoroughly studied by one of these parenteral routes. Oral and percutaneous studies were performed when effectiveness via these routes was of Interest. 

The induction of an immune response by various mucosal routes is an important approach for the control of mucosally acquired infections. The apparent linked nature of the mucosal immune system enables the delivery of an antigen to any mucosal surface to have the secondary effect of potentially inducing immunity at others. Induction of a combination of systemic and secretory immune responses can be determined by the nature of the antigen, the route of administration, and the delivery system utilized. For example, traditional parenteral vaccines primarily induce IgM and IgG responses, whereas mucosal vaccination can elicit both IgG and secretory IgA responses (Corthesy, 2007). 

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