Intravenous administration of drug

In pharmaceutical preparations, soybean oil emulsions are primarily used as a fat source in total parenteral nutrition (TPN) regimens. Although other oils, such as peanut oil, have been used for this purpose, soybean oil is now preferred because it is associated with fewer adverse reactions. Emulsions containing soybean oil have also been used as vehicles for the oral and intravenous administration of drugs drug substances that have been incorporated into such emulsions include amphotericin, " diazepam, retinoids, vitamins, poorly water-soluble steroids, fluorocarbons, and insulin. In addition, soybean oil has been used in the formulation of many drug delivery systems such as liposomes, microspheres, dry emulsions, self-emulsifying systems, and nanoemulsions and nanocapsules. ... 

Most drugs entering the systemic circulation require a finite time to distribute completely throughout the body. This is particularly obvious upon rapid intravenous administration of drugs. During this distributive phase, the drug concentration in plasma will decrease more rapidly than in the post-distributive phase. Whether or not such a distributive phase is apparent will depend on the frequency with which blood samples are collected. A distributive phase may last for few minutes, for hours or, very rarely, even for days. 

After intravenous administration of drugs that are extensively metabolized in the Kver (blood-flow-Kmited elimination see Section 6.2.4 for details), Eq. (6.22) can be simplified to... 

Intravenous administration of a drug produces the most rapid drug action. Next in order of time of action is the intramuscular route, followed by the subcutaneous route Giving a drug orally usually produces the slowest drug action. 

Figure 39.4a represents schematically the intravenous administration of a dose D into a central compartment from which the amount of drug Xp is eliminated with a transfer constant kp. (The subscript p refers to plasma, which is most often used as the central compartment and which exchanges a substance with all other compartments.) We assume that mixing with blood of the dose D, which is rapidly injected into a vein, is almost instantaneous. By taking blood samples at regular time intervals one can determine the time course of the plasma concentration Cp in the central compartment. This is also illustrated in Fig. 39.4b. The initial concentration Cp(0) at the time of injection can be determined by extrapolation (as will be indicated below). The elimination pool is a hypothetical compartment in which the excreted drug is collected. At any time the amount excreted must be equal to the initial dose D minus the content of the plasma compartment Xp, hence ...

Rats were implanted with indwelling jugular cannulae for intravenous (IV) administration of drugs (Weeks and Davis 1964). To monitor cortical EEG and electromyographic (EMG) activity, respectively, they were also prepared with chronic cerebrocortical electrodes and temporalis muscle electrodes (Khazan 1975). One week was allowed for recovery from surgery before experimentation. 

Parenteral administration of drugs by intravenous (IV), intramuscular (IM), or subcutaneous (SC) routes is now an established and essential part of medical practice. Advantages for parenterally administered drugs include the following rapid onset, predictable effect, predictable and nearly complete bioavailability, and avoidance of the gastrointestinal (GI) tract and, hence, the problems of variable absorption, drug inactivation, and GI distress. In addition, the parenteral route provides reliable drug administration in very ill or comatose patients. 

The major routes of parenteral administration of drugs are subcutaneous, intramuscular, and intravenous. Other more specialized routes are intrathecal, in-tracistemal, intra-arterial, intraspinal, intraepidural, and intradermal. The intradermal route is not typically used to achieve systemic drug effects. The major routes will be discussed separately. Definitions of the more specialized routes, along with additional information concerning needle sizes, volumes typically administered, formulation constraints, and types of medication administered, are summarized in Table 1. 

Rapid intravenous administration of this drug causes hypocalcemic tetany... 

The disposition of bromocriptine has been studied in several animal species and man following single oral and intravenous administration of the drug labelled with either tritium or carbon-14. 

Almost 30 routes exist for administration of drugs to patients, but only a handfbl of these are commonly used in preclinical safety studies (Gad, 1994). The most common deviation from what is to be done in clinical trials is the use of parenteral (injected) routes such as IV (intravenous) and SC (subcutaneous) deliveries. Such injections are loosely characterized as bolus (all at once or over a very short period, such as five minutes) and infusion (over a protracted period of hours, days, or even months). The term continuous infusion implies a steady rate over a protracted period, requiring some form of setup such as an implanted venous catheter or infusion port. 

Jendbro M, Johansson C-J, Strandberg P, Falk-Nilsson H, Edsbacker S (2001) Pharmacokinetics of budesonide and its major ester metabolite after inhalation and intravenous administration of budesonide in the rat. Drug Metab Dispos 29 769-776. 

After either oral or intravenous administration of ondansetron to laboratory animals the elimination of the drug is rapid. The short elimination half-lives t ji Table 7.7) reflect the high plasma clearance (CLp) in these species. Renal clearance (CLr) is below glomerular filtration rate, indicating that the major component of systemic clearance is metabolism. Ondansetron is rapidly absorbed after oral administration, peak concentrations in plasma being achieved within 40 min of dosing. However, the oral bioavailability is low. The similarity between concentrations of total drug-related material in plasma after oral and intravenous doses indicates that the low... 

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