Action, drug

Drugs are usually first distributed in the blood and then carried to tissues and organs whose cells they may be required to penetrate. A drug must have a suitable balance of hydrophilic and hydro-phobic character - the former to ensure sufficient solubility and the latter to ensure penetration of the phospholipid bilayer of the cell membrane. 

All drug action is likely, at some stage, to involve interaction with the many phosphorus compounds already present in the body. In many cases, this is known to be cellular DNA. Drug action can involve interference with DNA replication, the synthesis of cell walls, proteins or essential enzymes, or the function of ion channels and receptors [7,8]. Synthetic oligonucleotides and oligopeptides show much promise as drugs capable of interacting with body DNA (or RNA). 

Some drugs, called pro-drugs, are not effective in their initial formulation, but become active only after being metabolised in another part of the body, for example, the liver. An early example of this is prontosil, introduced in the 1930s, which is metabolised to the active form, sulphanil-amide (12.123)  

AZT (which is devoid of P) is metabolised as its triphosphate. Cyclophosphamide is metabolised in the liver to the active form which is known as phosphoramide mustard (12.124)  

The introduction of penicillin (a non-P compound) around the mid-twentieth century probably represented the next most notable achievement for chemotherapy. 

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Table 10.4-1, Drug targets and mechanisins of drug action.

MacKay, D. (1977). A critical survey of receptor theories of drag action. In Kinetics of drug action, edited by J. M. Van Rossum, pp. 255—322. Springer-Verlag, Berlin. 

In some cases the unwanted enantiomer can perturb other biological processes and cause catastrophic side effects. The use of enantiomerically pure compounds thus permits more specific drug action and the reduction in the amount of drug administered. Even in the cases where the other enantiomer is inactive, the work involved in its metabolism before secretion can be avoided. 

Meltzer HY (1999) The role of serotonin in antipsychotic drug action. Neuropsychopharmacology 21 106S—115S... 

The main goal of the Encyclopedia is to provide up-to-date information on the molecular mechanisms of drug action. Leading experts in the field have provided 159 essays, which form the core structure of this publication. 

Apart from very few exceptions, the entries in the main text do not contain drug names in their titles. Instead, drugs that are commonly used all over the world are listed in the Appendix. Also included in the Appendix are four-extensive sections that contain tables listing proteins such as receptors, transporters or ion channels, which are of particular interest as drug targets or modulators of drug action. 

Identify factors that influence drug action. 

Discuss the nursing implications associated with drug actions, interactions, and effects. 

The pharmaceutic phase of drug action is the dissolution of the dmg. Drugs must be in solution to be absorbed. Dmgi that are liquid or drugs given by injec-... 

Fhtients with kidney disease may exhibit drug toxicity and a longer duration of drug action. The dosage of drugp may be reduced to prevent the accumulation of toxic levels in the blood or further injury to the kidney. 

Intravenous administration of a drug produces the most rapid drug action. Next in order of time of action is the intramuscular route, followed by the subcutaneous route Giving a drug orally usually produces the slowest drug action. 

A drug administered by the intravenous (IV) route is given directly into die blood by a needle inserted into a vein. Drug action occurs almost immediately. 

Discuss the uses, general drug actions, and general adverse reactions, contraindications, precautions, and interactions of the sulfonamides. 

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