Fixed-dose

Dosing Fixed 180 mcg/wk subcutaneously Weight dependent 1.5 rncg/kg/wk... 

III. Kinetics of Fixed-Dose, Fixed-Time-Interval Regimens... 

III. KINETICS OF FIXED-DOSE, FIXED-TIME-INTERVAL REGIMENS... 

Most drugs that are administered on an outpatient basis are taken orally on a fixed-dose fixed-time interval regimen, for example, a specific dose, taken one, two or three times daily. In contrast to intravenous injection, orally administered drugs may be absorbed slowly, and the plasma concentration of the drug is influenced by both the rate of absorption and the rate of drug elimination (Figure 2.6). 

Antimony attaches oxygen in an invariable dose fixed by Nature, and the power of augmenting or diminishing which is not given to man il s en attache une dose invariablement fixee par la nature, et qu il n est pas donne a rhomme de pouvoir augmenter ou diminuer. In reply to a criticism by Berthollet, Proust says ... 

Phenytoin s absorption is slow and variable yet almost complete absorption eventually occurs after po dosing. More than 90% of the dmg is bound to plasma protein. Peak plasma concentrations are achieved in 1.5—3 h. Therapeutic plasma concentrations are 10—20 lg/mL but using fixed po doses, steady-state levels are achieved in 7—10 days. Phenytoin is metabolized in the fiver to inactive metabolites. The plasma half-life is approximately 22 h. Phenytoin is excreted primarily in the urine as inactive metabolites and <5% as unchanged dmg. It is also eliminated in the feces and in breast milk (1,2). Prolonged po use of phenytoin may result in hirsutism, gingival hyperplasia, and hypersensitivity reactions evidenced by skin rashes, blood dyscrasias, etc... 

In another incident a backhoe ruptured a 3-in. polyethylene natural gas pipeline fortunately the gas did not ignite. The drawings were complex and cluttered, and the contractor overlooked the pipeline. A metal detector was not used. This would have detected the pipe as a metal wire was fixed to it, a good practice. In a third incident a worker was hand-digging a trench, as an electric conduit was believed to be present. It was actually an old transfer line for radioactive waste, and he received a small dose of radioactivity. The planner had misread the drawing. 

Table 7 reveals that the grafting of TAC onto PE decreases the equilibrium contact angles of water and formamide from 92° to 65° and from 75° to 53°, respectively. This decrease is a function of the monomer level and the irradiation dose. At a fixed irradiation dose of 15 Mrad, variation of the TAC level from 0.5 to 3 parts causes a reduction in the contact angles of water by 13° (from 88° to 75°) and of formamide by 11° (from 72° to 61°). This is due to the fact that the concentration of... 

Estrogens and progestins (combination oral contraceptives) are used as oral contraceptives. There are three types of estrogen and progestin combination oral contraceptives monophasic, biphasic, and triphasic. The monophasic oral contraceptives provide a fixed dose of estrogen and progestin throughout the cycle The biphasic and triphasic oral contraceptives deliver hormones similar to the levels naturally produced by the body (Table 52-1). 

FIGURE 31.8 Change in the coefficient of friction of modified dicumyl peroxide/ethylene-propylene-diene monomer (DCPD/EPDM) with the concentration of trimethylolpropane triacrylate (TMPTA) at a fixed irradiation dose of 100 kGy. (G) Surface modified with 100 kGy, (A) Bulk modified with 100 kGy dose, ( ) Control EPDM rubber. (Erom Sen Majumder, P. and Bhowmick, A.K., Wear, 221, 15, 1998. With permission.)... 

Beasley C, Sanger T, Satterlee W, et al (1996a). Olanzapine vs placebo results of a double blind fixed dose olanzapine trial. Psychopharmacology 24, 159—67. 

Chouinard G, Jones B, Remington G, et al (1993). A Canadian multicentre placebo controlled study of fixed doses of risperidone and haloperidol in the treatment of chronic schizophrenic inpatients./Clin Psychopharmacol25—40. 

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