Intravenous bolus administration single dose

The disposition kinetics of diclofenac was determined in awake Beagle dogs after single Intravenous bolus administration of a 4 mg dose. The intravenous dose was administered into the left cephalic vein. Blood samples (3 ml) were drawn from the vein in the opposite leg at intervals over 30 h after dosing. These samples were heparinized and centrifuged immediately to isolate the plasma fraction. Samples were stored frozen until analyzed. 

Tse and Szeto (1982) reported on the bioavailability of theophylline following single intravenous bolus and oral doses in beagle dogs (Table P3.1). Plasma theophylline concentrations after intravenous and oral administration were described by a one-compartment open model. The doses administered were as follows ... 

Dosages and routes of administration Naloxone is only used parenterally, mostly as an intravenous bolus or by infusion. The compound is used in single or repetitive doses of 0.4-2 mg up to a total dose of 10 mg. 

Therapeutic Uses Muromonab-CD3 is indicated for treatment of acute organ transplant rejection. The recommended dose is 5 mg/day (in adults less for children) in a single intravenous bolus (<1 minute) for 10-14 days. Antibody levels increase over the first 3 days and then plateau. Circulating T cells disappear from the blood within minutes of administration and return within 1 week after cessation of therapy. Repeated use of muromonab-CD3 results in the immunization of the patient against the mouse determinants of the antibody, which can neutralize and prevent its immunosuppressive efficacy. Thus, repeated treatment with the muromonab-CD3 or other mouse monoclonal antibodies generally is contraindicated. 

Because considerable time may elapse before a steady-state condition is attained as a result of repeated drug administration, it often is desirable to administer a large dose initially (i.e., loading dose) to achieve the desired drug levels immediately. Equation 9.42, which describes the time course of drug concentration after a single intravenous bolus dose, may be written as... 

While a single intravenous bolus dose of a drug may produce the desired therapeutic concentration and, therefore, the desired pharmacological effect immediately, this mode of administration is unsuitable when it is necessary to maintain plasma or tissue concentrations at a concentration that will prolong the duration of this effect. We are interested in reaching the therapeutic... 

Figure 11.1 illustrates a typical plasma concentration versus time profile following the administration of a single intravenous bolus dose of a drug that follows first-order elimination and one-compartment distribution. 

Equation 11.21 and Eq. 11.16 both equal Xq/ VK. Therefore, Eq. 11.21 for (AUC)o (following the administration of a single intravenous bolus dose) is equivalent to Eq. 11.16, an equation for (AUC)5 during dosing interval at steady state. Therefore, (AUC)5 at steady state is equivalent... 

And since dose/V X = (AUC)o following the administration of a single intravenous bolus dose, substituting for the term dose/WC in Eq. 11.17 with the term (AUC)o yields the following equation ... 

Figure 11.8 Plasma concentration (Cp) versus time profile following the administration of a single dose and multiple doses of a drug as intravenous bolus, min, minimum max, maximum av, average.

It will be very helpful to begin to compare Eq. 11.12 (for an intravenous bolus) and Eq. 12.13 (for extravascularly administered dose) for similarity and differences, if any, and identify the commonality between the two equations. It may he quickly apparent that the information obtained following the administration of a single dose of a drug, either intravenously or... 

Figure 12.3 Semilogarithmic plots of plasma concentration (Cp) versus time profiles following the administration of a single dose of a drug as an intravenous bolus (a) and byanextravascular route (b).>(o, the dose F, fraction of administered dose that is available to reach the general circulation and K, first-order absorption and elimination rate constants, respectively V, apparent volume of distribution.

Etomidate inhibits adrenal function resulting in reduced steroidogenesis after administration of both single boluses and maintenance infusions (397). In a prospective cohort study of 62 critically ill patients who were mechanically ventilated for more than 24 hours, about half developed adrenal insufficiency on the day after intubation. Administration of a single intravenous dose of etomidate 0.2-0.4 mg/kg for intubation led to a 12-fold increased risk of adrenal insufficiency (398). Etomidate should therefore be avoided as an induction agent in critical illness, in particular in patients with septic shock, among whom the incidence of adrenal insufficiency is high (399,400,401). 

One dosing cohort received 75 U kg rhAT, and the other cohort received a normal sahne placebo (both as single bolus intravenous injection). Heparin resistance was defined as failure to achieve an ACT of >480 seconds after receiving a total dose of 400 U kg heparin intravenously after anesthesia induction and surgical incision, but just prior to CPB. The proportion of rhAT patients who required administration... 

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