Drugs multiple

Although the efficacy of tricyclic antidepressants in the treatment of unipolar depression is beyond reproach, the side-effect profile of these agents makes them less desirable as first-line therapeutic agents. Introduction of selective serotonin reuptake inhibitors (SSRIs) such as fluoxetine, paroxetine, sertraline, citalopram and fluvoxamine in the past decade has revolutionized the treatment of depression universally. The side-effect profile of SSRIs, such as nausea, diarrhea and sexual dysfunction, is considerably more benign than that of tricyclic drugs. Multiple controlled trials have proven the efficacy of SSRIs vs. placebo (Nemeroff, 1994). Recently, a number of SNRIs (serotonin and noradrenaline reuptake inhibitors) and so-called atypical antidepressants have been marketed that may have additional advantages over SSRIs, such as more rapid onset of action (venlafaxine. mirtazapine) and low sexual side-effect potential ( bupropion, nefazodone). Additionally, it appears that venlafaxine may be more efficacious in cases of treatment-refractory depression (Clerc et al., 1994 Fatemi et al., 1999). Finally, in a recent report (Thase et al., 2001),... 

The threshold dosage of phenylephrine in the average adult has been estimated to be 0.4 mg intravenously, 2 mg subcutaneously, and 50 mg orally. The upper limit for safe dosage in normal adults is approximately 1.5 mg intravenously and 300 mg subcutaneously. Because a 50-ml drop of 10% phenylephrine contains 5 mg of drug, multiple applications can result in overdosage, especially if absorption from the site of administration is enhanced or if the patient is compromised by age, body size, use of concomitant medications, or trauma. Furthermore, the extent of the absorption into the systemic circulation of topically applied phenylephrine is unknown because absorption has been shown to be possibly diminished due to local vasoconstriction. 

Vatier J, Vallot T, Farinotti R. Antacid drugs multiple but too often unknown pharmacological properties./ Pharm Clin 1996 15(1) 41-51. 

C. Mechanisms of Action The general effect of antiseizure drugs is to suppress repetitive action potentials in epileptic foci in the brain. Different mechanisms are involved in achieving this effect. In the case of some drugs, multiple mechanisms may contribute to their antiseizure activities. Some of the recognized mechanisms are described below. 

Sastry, B. V. R. (1991). Placental toxicology Tobacco smoke, abused drugs, multiple chemical interactions and placental function. Repnod. Fertil. Dev. 3, 355-372. 

In light of a high degree of structural variability of drugs, multiplicity of kinetics and metabolite kinetics, the task of establishing a clear correlation between the structured chemistry of substituents and their pharmacokinetic properties appears somewhat daunting. The pharmacokinetic fate of a drug molecule, however, appears to be a consequence of its physicochemical properties and, therefore, may, to some extent, be predicted from its chemical structure. 

Accurate, precise isotope ratio measurements are important in a wide variety of applications, including dating, examination of environmental samples, and studies on drug metabolism. The degree of accuracy and precision required necessitates the use of special isotope mass spectrometers, which mostly use thermal ionization or inductively coupled plasma ionization, often together with multiple ion collectors. 

Infectious patients present a difficult challenge when trying to protect health care workers. These patients must be isolated from the health care workers as well as from the other patients in the hospital. Special isolation rooms are used for this purpose. These rooms are generally used for isolation of infectious tuberculosis (TB) patients, but could be used for patients with other airborne-transmitted diseases. In the United States, there were 22 812 new cases of tuberculosis in 1993, equal to 8.7 per 100 000 population. This represents a 2.8% increase since 1985, following a 6-7% annual decline from 1981-1984.Several studies have documented higher than expected tuberculin skin test (TST) conversion rates in hospital personnel.The National Institute for Occupational Safety and Health " reports that multiple-drug-resistant (MDR) strains of TB have been reported in 40 states and have caused outbreaks in at least 21 hospitals, with 18-35% of exposed workers having documented TST conversions. 

As well as complex biological targets, complex chemical targets (drugs with multiple activity, prodrugs) can be used to produce therapeutically useful phenotypic responses. 

Bendamustine is a useful antineoplastic drug for the treatment of non-Hodgkin s lymphomas, multiple myeloma and as a partner drug in the combination therapy of some solid tumors. The cross-resistance with other alkylating drugs is not complete. Myelosuppression and lymphocytopenia is its main dose-limiting toxicity. 

Acquired resistance has been observed by constitutive upregulation of mdr efflux pump expression due to a mutation inactivating a respective repressor or inducibly, caused by molecules transiently inactivating repressor molecules upon binding. Depending upon the substrate spectra of the respective subset of efflux pumps upregulated, a multiple drug resistance (mdr) phenotype is expressed, which in combination with a specific resistance mechanism can contribute to a clinically relevant level of resistance. 

Antidepressant Drugs. Figure 1 Effects of stress as a model for depression and the reversal by the use of antidepressants. Multiple intracellular targets might be involved in the regulation of plasticity and resilience by antidepressants, which block extracellular transporters. Adapted from [1],... 

Criteria for initiation of drug treatment now take into consideration total cardiovascular risk rather than blood pressure alone, such that treatment is now recommended for persons whose blood pressure is in the normal range but still bear a heavy burden of cardiovascular risk factors. Thus, the role of simultaneous reduction of multiple cardiovascular risk factors in improving prognosis in hypertensive patients is stressed. In addition, more aggressive blood pressure goals are recommended for hypertensive patients with comorbid conditions such as diabetes mellitus or renal insufficiency. 

Resistance of P. vivctx to chloroquine occurs, but is geographically limited. P. vivctx and P. ovale produce hypnozoites, parasite stages in the liver that can produce multiple relapses. The drug of choice for blood stage infections to date remains chloroquine for all three species. To achieve radical cure of P. vivctx and P. ovale infection, this must be followed by primaquine. 

Bisphosphonates have been shown to be highly effective in osteoporosis, cancer bone metastasis, multiple myeloma, and Paget s disease of bone. While generally very well tolerated, these drugs do have potential adverse effects. Recently, the association of long-term high dose bisphosphonate treatment with osteonecrosis of the jaw has been described. This is a potentially serious side effect seen mostly in patients with multiple myeloma or... 

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