Culture: Considerations in drug therapy

• Pharmacogenetics accounts for individual variation in the response to drug therapy. This variation is related to genetic alterations known as polymorphisms. Understanding the unique genetic makeup of an individual patient can ideally allow custom tailoring of the dose of a drug to promote therapeutic effect and prevent adverse effects. Pharmacogenetics is a new fi eld, and knowledge about genetic variations affecting drug therapy is still somewhat limited, although it is rapidly growing. Some pharmacogenetic differences are inherited along ethnic or racial lines; other differences are unique to people and not inherited by ethnicity or race. • Pharmacogenomics examines how all genes can affect drug therapy. The hope is that by understanding human genome variations, drugs can be developed that are more effective in different patient populations and predictions can be made concerning whether or not patients will have altered pharmacologic responses to a drug. • Genetic variations of specifi c P-450 isoenzymes are known to infl uence drug metabolism. The variations include ultrarapid metabolizers, extensive metabolizers, intermediate metabolizers, and poor metabolizers. Ultra-rapid metabolizers biotransform drugs using a particular isoenzyme more rapidly and thus may be at risk for subtherapeutic system levels of a prescribed drug. Poor metabolizers do not biotransform drugs using that isoenzyme, which means that systemic drug levels will rise higher than anticipated, producing more adverse effects. • Genotype testing is now available for some of the P-450 isoenzymes and is used in clinical practice for some drugs. • Many cultural groups in North America embrace both their original culture and the dominant North American culture. • Although generalizations may be made about the beliefs of different cultural groups, these statements cannot be applied to all people sharing a cultural background. Every person must be assessed to determine his or her unique beliefs. • Individual health-seeking behaviors and health practices exist and differ, sometimes markedly, among the major cultural groups in the United States. • Medicinal plants and symbolic rituals play important roles in the health practices of many cultural groups. • Patients should be advised of the potential for chemical interactions between folk medicine or herbal remedies and traditional (Western) drug therapy. • Factors related to communication, time, and environmental control infl uence the relationship between the nurse and the patient whose backgrounds are culturally different. • Individual variation in response to the effects of drugs and pharmacokinetic drug differences may occur because of biologic and genetic differences among people. For example, some patients may metabolize certain drugs more slowly because of a genetically induced enzyme defi ciency. • Nursing management emphasizes a thorough assessment of a patient's health beliefs, traditional practices, and cultural infl uences, so that the nurse and other health care providers may implement interventions that complement the patient's values. Therapeutic regimens that accommodate a patient's cultural values (and traditional rituals) are more likely to foster adherence to drug therapy and discourage alienation from the health care system. • Cultural, ethnic, and environmental infl uences add complex issues to pharmacotherapy.