Dosing intravenous

Anistreplase has a considerably longer a half-life than streptokinase, ie, 90 min compared to 20 min (87,88). Moreover, it does not require prolonged infusion to achieve its thrombolytic effects. Anistreplase was found to be highly effective after a single intravenous dose of 30 units over a 5-min period compared to a 60-min infusion of 1.5 million units of streptokinase (89—94). In direct comparative studies, anistreplase was as effective as intracoronary (95,96) and intravenously (96—100) adrninistered streptokinase. In a randomized, double-blind, placebo-controUed study (AIMS trial) with 1004 patients given this modified enzyme, the 30-day mortaUty rate was 12.2% for patients receiving placebo, compared to 6.4% for patients who received 30 units of anistreplase intravenously within six hours of the onset of symptoms (101). 

Alimentary biotin deficiency is rare. It may, however, occur in patients on long-term parenteral nutrition lacking biotin or in persons who frequently consume raw egg white. Raw egg white contains a biotin-binding glycoprotein, called avidin, which renders biotin biologically unavailable. Pharmacological doses of the vitamin (1-10 mg/d) are then used to treat deficiency symptoms. There are no reports of toxicity for daily oral doses up to 200 mg and daily intravenous doses of up to 20 mg [2]. 

The elimination half-life after oral dosing is longer than after intravenous dosing (TU2po > TU2iv) when the so-called flip-flop condition applies (Ka < Ke). 

According to the law of corresponding areas (FH Dost), the area derived from the integrated Bateman function (AUCpo = AUCiv) is the same as the area after-intravenous dosing if the bioavailability (F) is complete. 

The systemically available fraction or bioavailability (F) can be defined by the fraction of the area after- oral and intravenous dosing, respectively. 

The first study to demonstrate the activity of enfuvirtide in HIV-infected patients (Kilby et al. 1998) showed that patients receiving the maximum 100 mg intravenous dose had maximum median declines in HIV-1 RNA of -1.96 logjo copies/mL through 14 days. Several additional studies (Kilby et al. 2002 Lalezari et al. 2003a, b) further demonstrated the safety and efficacy of enfuvirtide and led to the selection of twice-daily subcutaneous injections of a 90 mg nominal dose for testing in the TORO (T-20 vs. optimized regimen only) pivotal clinical trials. 

C22-0075. A patient weighing 65 kg is given an intravenous dose of Tc, a radioactive isotope that... 

Microplasmin is a truncated form of plasmin that is more resistant to the effects of antiplasmin. In a rabbit stroke model, intravenous microplasmin infusion resulted in a high rate of clot lysis without increasing the rate of ICH. In addition, there was significant improvement in the behavioral rating scores, suggesting a neu-roprotective effect. The ongoing MITI-IV trial is a 40-patient multicenter, double-blind, placebo-controlled trial using three different intravenous doses of microplas-min to treat acute ischemic stroke (NIHSS >6 and <22) within 12 hours of symptom onset. 

Classically, to measure absolute absorption the plasma area imder the curve from an intravenous dose would be compared to that caused by the feeding of an oral dose. However, the carotenoids are lipid-soluble and are normally incorporated in chylomicrons synthesised in the enterocytes, a situation that cannot be replicated and applied to studies in humans because an intravenous preparation that would behave naturally is not possible. 

The mean residence time MRT can thus be defined as the time it takes for a single intravenous dose to be reduced to 36.8% in a one-compartment open model. This follows from the property derived above in eq. (39.105) and from eq. (39.5) ... 

This relationship shows the analogy with the previously derived half-life time r,/2 (in Section 39.1.1), which is the time required for a single intravenous dose to be halved in a one-compartment open system. Since we already derived in eq. (39.9) that ... 

FIGURE 6. Histograms depicting doses of PCP and related compounds which produced (A) maximal disruption of rotarod performance (B) loss of righting reflex (C) clonic and/or toxic convulsions and (D) lethality in rats (n=6) given cumulative intravenous doses... 

Atropine, epinephrine, and lidocaine can be administered through the tracheal tube before venous access is achieved at 2-2.5 times the recommended intravenous dose diluted with 10 mL of normal saline or sterile water. Stop CPR, administer beyond the tip of the endotracheal tube, follow with five quick insufflations to aerosolize the drug, and then resume CPR. 

Followed 5 minutes later by a second 5 mg IV dose then 50-100 mg orally every day initiated 1-2 hours after the intravenous dose... 

In patients receiving infliximab, monitor for infusion-related reactions such as hypotension, dyspnea, fever, chills, or chest pain when administering intravenous doses. 

Adults 1 5-20 mg/kg single intravenous dose or divided oral dose Infants less than 3 months 1 0-15 mg/kg single intravenous dose Neonates 1 5-20 mg/kg single intravenous dose Maintenance dose ... 

Epidural analgesia is frequently used for lower extremity procedures and pain (e.g., knee surgery, labor pain, and some abdominal procedures). Intermittent bolus or continuous infusion of preservative-free opioids (morphine, hydromorphone, or fentanyl) and local anesthetics (bupivacaine) may be used for epidural analgesia. Opiates given by this route may cause pruritus that is relieved by naloxone. Adverse effects including respiratory depression, hypotension, and urinary retention may occur. When epidural routes are used in narcotic-dependent patients, systemic analgesics must also be used to prevent withdrawal since the opioid is not absorbed and remains in the epidural space. Doses of opioids used in epidural analgesia are 10 times less than intravenous doses, and intrathecal doses are 10 times less than epidural doses (i.e., 10 mg of IV morphine is equivalent to 1 mg epidural morphine and 0.1 mg of intrathecally administered morphine).45... 

Syrup/suspension/ solution Extended-release/ enteric-coated tablets Faster rate of absorption 100% Delayed absorption 60-90% Faster rate of absorption Delayed absorption 89% of the suspension and less than regular-release tablets Unknown NA Faster rate of absorption than tablets Extended-release 90% of intravenous dose. Delayed-release 81-90% of intravenous dose Delayed absorption with delayed-release tablets valproate is rapidlyconverted to VPA in the stomach, then is rapidly and almost completely absorbed from the Gl tract NA NA... 

Etoposide causes multiple DNA double-strand breaks by inhibiting topoisomerase II. The pharmacokinetics of etoposide are described by a two-compartment model, with an a half-life of 0.5 to 1 hour and a (5 half-life of 3.4 to 8.3 hours. Approximately 30% of the dose is excreted unchanged by the kidney.16 Etoposide has shown activity in the treatment of several types of lymphoma, testicular and lung cancer, retinoblastoma, and carcinoma of unknown primary. The intravenous preparation has limited stability, so final concentrations should be 0.4 mg/mL. Intravenous administration needs to be slow to prevent hypotension. Oral bioavailability is approximately 50%, so oral dosages are approximate two times those of intravenous doses however, relatively low oral daily dosages are used for 1 to 2 weeks. Side effects include mucositis, myelosuppression, alopecia, phlebitis, hypersensitivity reactions, and secondary leukemias. 

Guinea pig, neonate— adult 241 Am citrate aqueous solution, single dose applied to tongue, 0.6-0.9 pig/kg % 1.1 0.55 0.19 0.17 0.06 0.03 0.02 0.005 Age 0.5 d 1 d 5 d 10 d 15 d 20 d 30 d adult Absorption estimate based on comparisons with liver and carcass 241 Am after an intraperitoneal dose (neonates) or intravenous dose (adults), with adjustment for excretion Bomford and Harrison 1986... 

Rat, adult 241 Am in wild molluscs or241 Am nitrate injected into mollusc tissue, twice weekly for 8 weeks 0.026-0.12 (wild mussels) 0.016-0.040 (injected mussel) Absorption estimate based on comparisons with liver and carcass 241 Am after an intravenous dose, with adjustment for excretion, twice weekly for 8 weeks Harrison et al. 1988... 

Fate. Preliminary investigations directed at adapting the method of Averell and Norris (2) to the analysis of animal tissues indicated that if precautions were taken to avoid emulsions the method could be used satisfactorily. Tissue samples of about 5 grams were most convenient, and the usual reagent and tissue blanks were run simultaneously. Following the administration of an acutely lethal intravenous dose to a dog it was found that parathion could be recovered from the urine, liver, bile, kidney, spleen, and lung. 

Fig. 20 Percentage xylose dose recovered in urine as a function of age after a 5 g intravenous dose (A), 5 g oral dose (B), and 25 g oral dose (C). Line D is the ratio of urinary recoveries (oral to intravenous) after 5g doses (y-axis on right). Symbols represent data obtained from different studies. (From Ref. 155.)...

Figure 9 Plasma profile of L-a-methyldopa following intravenous dose of L-a-methyl-dopa and jejunal dose of L-a-methyldopa-phenylalanine and L-a-methyldopa (n = 6-7). ( ) L-a-methyldopa following jejunal dose of prodrug (V) L-a-methyldopa jejunal dose ( ) L-a-methyldopa intravenous dose.

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