Administration, drugs intravenous route

Drugs are administrated by intravenous routes or ex-travascular routes including oral, sublingual, subcutaneous, intramuscular, rectal (by enema or suppository), and transdermal. Available dosage forms include suspensions, immediate-release capsules or tablets, sustained-release capsules or tablets, and enteric-coated capsules or tablets that resist dissolution in the acidic pfi of the stomach. 

In this section the intraperitoneal route of liposome administration will be discussed. For a number of diseases this route of administration may be preferred over the intravenous route of administration of liposomes. For example, intraperitoneal injection of drug-... 

In comparison with the intravenous route of administration the potential advantages of intraperitoneal therapy are the avoidance of high toxic drug plasma levels and an increased (local) exposure of tumors (cells) to anticancer drugs. Whether this increased exposure... 

Aprotinin. Aprotinin is a naturally occurring serine protease inhibitor, has found widespread applications either by the intravenous route or as a component of biological sealants, because of its ability to decrease blood loss, and, as a consequence, transfusion requirements. Anaphylactic reactions are mediated by IgG and IgE antibodies. The risk of anaphylactic reactions has been estimated between 0.5 and 5.8% when used intravenously during cardiac surgery, and at 5 for 100,000 applications when used as a biologic sealant [25]. Patients previously treated with this drug present an increased risk and any new administration should be avoided for at least 6 months following an initial exposure [25]. 

Opioids maybe administered in a variety of routes including oral (tablet and liquid), sublingual, rectal, transdermal, transmucosal, intravenous, subcutaneous, and intraspinal. While the oral and transdermal routes are most common, the method of administration is based on patient needs (severity of pain) and characteristics (swallowing difficulty and preference). Oral opioids have an onset of effect of 45 minutes, so intravenous or subcutaneous administration maybe preferred if more rapid relief is desired. Intramuscular injections are not recommended because of pain at the injection site and wide fluctuations in drug absorption and peak plasma concentrations achieved. More invasive routes of administration such as PCA and intraspinal (epidural and intrathecal) are primarily used postoperatively, but may also be used in refractory chronic pain situations. PCA delivers a self-administered dose via an infusion pump with a preprogrammed dose, minimum dosing interval, and maximum hourly dose. Morphine, fentanyl, and hydromorphone are commonly administered via PCA pumps by the intravenous route, but less frequently by the subcutaneous or epidural route. 

For all commonly used routes of administration except intravenous, the drug must dissolve in body fluids and diffuse through one or more membranes to enter the plasma. Thus, all routes except intravenous are classed as extravascular routes, and absorption is defined as appearance of the drug in plasma. 

Thus, %F is defined as the area under the curve normalized for administered dose. Blood drug concentration is affected by the dynamics of dissolution, solubility, absorption, metabolism, distribution, and elimination. In addition to %F, other pharmacokinetic parameters are derived from the drug concentration versus time plots. These include the terms to describe the compound s absorption, distribution, metabolism and excretion, but they are dependent to some degree on the route of administration of the drug. For instance, if the drug is administered by the intravenous route it will undergo rapid distribution into the tissues, including those tissues that are responsible for its elimination. 

Borlak J, Blickwede M, Hansen T, Koch W, Walles M, Levsen K (2005) Metabolism of verapamil in cultures of rat alveolar epithelial cells and pharmacokinetics after administration by intravenous and inhalation routes. Drug Metab Dispos 33(8) 1108-1114... 

The absorption (following administration by oral, intramuscular and intravenous routes), distribution and elimination of the drug has been studied by radiotracer techniques in rats and rabbits [283, 284]. The substituted benzoic acid was labelled with and the alkanolamine remnant with Almost all radioactivity was recovered from the urine even after oral administration. 

A drug can be administered directly into the vascular compartment or by an alternative route, such as orally. It can usually be assumed that the entire dose administered by the intravenous route reaches the systemic circulation. After oral administration, only a proportion may reach the systemic circulation because of incomplete absorption or because absorbed drug may be metabolised in the mucosa of the gastrointestinal... 

FU has been extensively used in the treatment of skin cancers and a variety of solid tumours, such as breast, colorectal and gastric cancers, usually via intravenous (i.v.) administration. Although this route is generally the most efficient and the least toxic, it is costly and inconvenient [87], Furthermore, treatment of cancer with 5-FU has been found to cause neurotoxic and cardiotoxic side effects. Toxicity also derives from the lack of selectivity of the drug towards tumours, and resistance can occur if the cell produces excess of dump, for competing with the drug in the active site [88]. 

The most extensive experiments at Edgewood were done In 1963-1966 with DMHP acetate. Approximately 100 volunteers were given doses of a DMHP acetate racemic mixture during this period. Oral, Intramuscular, and Intravenous routes of administration were used. Oral doses ranged from 3 to about 60 vg/kg. Intravenous doses ranged from 0.5 ug/kg to (In a few subjects) 5 pg/kg. Intramuscular doses were between 0.5 and 5 yg/kg, Most subjects received only one drug exposure, and a few had multiple exposures, but rarely more than two. 

Intravenous route is the most rapidly effective and the desired blood concentration can be obtained with a definite dose but at the same time it is the most dangerous route of administration. For once the drug is injected there is no retreat. So, intravenous injection must usually be performed slowly and with constant monitoring of the patient. This route is usually reserved for emergencies when a rapid action is required and infusion of large amounts of fluids to overcome dehydration or to supply nutrition to patients who can not take food/fluids orally. 

Some of the dosage formulations available for protein pharmaceuticals are listed in Table 5.7. An examination of Table 5.7 reveals that no protein drug up until this time has been formulated for oral administration. Most protein drugs are administered by means of injection (parenteral administration). Parenteral administration includes intravenous, intra-arterial, intracardiac, intraspinal or intrathecal, intramuscular, intrasynovial, intracuta-neous or intradermal, subcutaneous injections, and injection directly into a dermal lesion (e.g., a wart). The parenteral route of administration requires a much higher standard of purity and sterility than oral administration. It also may require trained... 

Bioavailability refers to the portion of a drug absorbed from the site of administration. The reference site of administration is intravenous, because this route produces 100% absorption. Figure 3-1 illustrates three sample drug concentration curves in plasma as a function of time. The area under the curve (AUC) is the total amount of drug in the systemic circulation available for distribution to the sites of action. The same dose completely absorbed from any of these routes would produce an identical area under the curve (i.e., 100% bioavailability), although the shape would differ. 

Administration of fibrinolytic drugs by the intravenous route is indicated in cases of pulmonary embolism with hemodynamic instability, severe deep venous thrombosis such as the superior vena caval syndrome, and ascending... 

EXTENSIONS AND COMMENTARY This quotation is from a paper by Martin and Sloan, published almost thirty years ago, that stands as our only measure of the human response to tryptamine. The first of the two reports in the comments took place 5 years earlier, with depressed patients and at very low levels of drug administration. It had already been established in rat and dog studies that tryptamine was known to enter the brain but, due to rapid metabolism, had only a short duration of central activity. Hence, the researchers in both these studies chose to employ an intravenous route of administration. There are a number of valuable points to be made in this latter report describing the 250 mg. study. 

Many drugs can now be delivered rectally instead of by parenteral injection (intravenous route) or oral administration. Generally, the rectal delivery route is particularly suitable for pediatric and elderly patients who experience difficulty ingesting medication or who are unconscious. However, rectal bioavailabilities tend to be lower than the corresponding values of oral administration. The nature of the drug formulation has been shown to be an essential determinant of the rectal absorption profiles. The development of novel absorption enhancers with potential efficacy without mucosal irritation (low toxicity) is very important. The delivery of peptide and protein drugs by the rectal route is currently being explored and seems to be feasible. 

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