Drug interactions mechanisms

Li AP (1998) Scientific Basis of Drug-Drug Interactions Mechanism and preclinical evaluation. Drug Information Journal 32 657-664... 

Hansten, P. D., and J. R. Horn. 1990. Drug interaction mechanisms and clinical characteristics. In Drug interactions and updates. Vancouver, Wash. Applied Therapeutics. 

Drug-drug interaction Mechanism of interactions Reference... 

Li AP. Scientific basis of drug-drug interactions Mechanism and preclinical evaluation. Drug Inf J. 1998 32 657-664. 

Kramer G, Besser R, Theisohn M, Eichelbaum M. Carbamazepine-danazol drug interaction mechanism and therapeutic usefulness, Acta Neurol Sccmd( 9ZA) 70, 249. 

These, such as the black box that was the receptor at the turn of the century, usually are simple input/output functions with no mechanistic description (i.e., the drug interacts with the receptor and a response ensues). Another type, termed the Parsimonious model, is also simple but has a greater number of estimatable parameters. These do not completely characterize the experimental situation completely but do offer insights into mechanism. Models can be more complex as well. For example, complex models with a large number of estimatable parameters can be used to simulate behavior under a variety of conditions (simulation models). Similarly, complex models for which the number of independently verifiable parameters is low (termed heuristic models) can still be used to describe complex behaviors not apparent by simple inspection of the system. 

Following concurrent administration of two drugs, especially when they are metabolized by the same enzyme in the liver or small intestine, the metabolism of one or both drugs can be inhibited, which may lead to elevated plasma concentrations of the dtug(s), and increased pharmacological effects. The types of enzyme inhibition include reversible inhibition, such as competitive or non-competitive inhibition, and irreversible inhibition, such as mechanism-based inhibition. The clinically important examples of drug interactions involving the inhibition of metabolic enzymes are listed in Table 1 [1,4]. 

There are four distinct mechanisms of Interference In laboratory testing. Physical, chemical, pharmacological and drug-drug Interactions are of special Interest to the laboratory scientist. The mechanisms of the Interferences will be briefly reviewed and wherever possible, solutions suggested. 

The microorganisms do not necessarily always form the same metabolites as humans in a similar manner, but they can be useful for studies of drug interactions, disposition, etc. [11]. Although there is no correlation between the mammahan and microbial isozymes, the mechanism involved in microorganisms is still unknown, but may be similar to that involved in animals. Additionally, the fungal metabohsm of the compounds is often affected by the concentration, nutritional factors, inducers, and environmental factors [12]. 

Drug Mechanism of Action Loading Dose Daily Dose Drug Interactions... 

Mechanisms of action, effectiveness for specific seizure types, common adverse effects, and potential for drug interactions are key elements in selecting medications for individual patients. 

Each antidepressant has a response rate of approximately 60% to 80%, and no antidepressant medication or class has been reliably shown to be more efficacious than another 22 MAOIs may be the most effective therapy for atypical depression, but MAOI use continues to wane because of problematic adverse effects, dietary restrictions, and possibility of fatal drug interactions.22,28 There is some evidence that dual-action antidepressants, such as TCAs and SNRIs, may be more effective for inpatients with severe depression than are the single-action drugs such as SSRIs,22,28 but the more general assertion that multiple mechanisms of action confer efficacy advantages is quite controversial.33... 

Black cohosh has been one of the most studied herbal remedies for vasomotor symptoms, and it has not demonstrated a substantial benefit over placebo. The mechanism of action, safety profile, drug-drug interactions, and adverse effects of black cohosh remain unknown. In non-placebo-controlled trials conducted for 6 months or less, black cohosh demonstrated a small reduction in vasomotor symptoms. It has not been shown to be effective for vasomotor symptoms in women with breast cancer.33 There have been case reports of hepatotoxicity with the use of black cohosh.36 Caution should be exercised when considering the use of this product, especially in patients with liver dysfunction. 

Compare and contrast the currently available immunosuppressive agents in terms of mechanisms of action, adverse events, and drug-drug interactions. 

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