Polypharmacy

As can be seen in Table 4.2, many agents commonly co-prescribed with antipsychotics may act as inducers and inhibitors. That these agents are also prone to ethnically determined variations in their own metabolism, suggests that providing the optimal dose of antipsychotics in various ethnic groups may become complex where psychotropic polypharmacy is common. 

Janssen, B. et al. (2004). Validation of polypharmacy process measures in inpatient schizophrenia care. Schizophr. Bull., 30, 1023-33. 

Sim, K. et al. (2004). Antipsychotic polypharmacy in patients with schizophrenia a multicentre comparative study in East Asia. Br.. Clin. Pharmacol, 58, 178-83. 

CNS drugs, especially when several agents are used concomitantly (as in polypharmacy)... 

Bjerrum L, Sogaard J, Hallas J et al. (1998) Polypharmacy correlations with sex, age and drug regimen. A prescription database study. Eur J Clin Pharmacol 54(3) 197-202... 

Horne R and Weinman J (1999) Patients beliefs about prescribed medicines and their role in adherence to treatment in chronic physical illness. J Psychosom Res 47(6) 555-567 Kannisto V, Lauritsen J, Thatcher AR et al. (1994) Reductions in mortality at advanced age several decades of evidence from 27 countries. Population and development review 20(4) 793-810 Lazarou J, Pomeranz BH, Corey PN (1998) Incidence of adverse drug reactions in hospitalized patients a meta- analysis of prospective studies. JAMA 279(15) 1200-1205 LeSage J (1991) Polypharmacy in geriatric patients. Nurs Clin North Am 26(2) 273-290 Pitkala KH, Strandberg TE, Tilvis RS (2001) Is it possible to reduce polypharmacy in the elderly ... 

Other important factors for the increased risk of adverse drug reactions are polypharmacy and multimorbidity. Before adding a drug the physician should try to diagnose the condition and rule out drugs as the cause of the problem. When a drug is added the dose should be lower than in younger adults and then the dose can be titrated to a therapeutic response. 

Veehof L, Stewart R, Haaijer-Ruskamp F et al. (2000) The development of polypharmacy. A longitudinal study. Fam Pract 17(3) 261-267... 

Impaired balance and walking abilities Muscle weakness Use of fall-risk increasing drugs Use of polypharmacy (> 5 drugs)... 

Finally hold in mind that falls are frequent in old age and can lead to severe consequences, including sufferings both for the individual and the next of kin. Also the cost for the society of falls and fractures are considerable. Falls increase with the use of fall-risk-increasing drugs and polypharmacy and can be prevented by a multifactor approach including reassessing the medications used by older people. 

Many different drug classes have shown to cause hypotension and orthostatic reactions and drugs for cardiovascular conditions, psychoactive medicines and polypharmacy, can all have this side effect (Box 5.15). Among the most frequently used drugs in the elderly are diuretics, ACE-inhibitors, angiotensin II antagonists, calcium channel blockers and antidepressants. 

Falls increase with the use of fall-risk-increasing drugs and polypharmacy and can be prevented by improving the medications used by older people... 

Several of the individual problems and risks increasing and cumulating the risk for morbidity and mortality in the elderly are presented in this book. Each of them is presented in more detail elsewhere. Special attention should be given to patients with severe diseases, polypharmacy, high-alert medications, several prescribers, several acute hospital admissions, and low compliance. It is important to understand that the problems and risks are interconnected. One problem lead to another in a cascade, where the net benefit to harm relation, might be negative. 

Polypharmacy is often a consequence of the cascade of problems. A literature review found that polypharmacy continues to increase and is a known risk factor for important morbidity and mortality (Hajjar et al. 2007). The reviewers states that many studies have found that various numbers of medications are associated with negative health outcomes, but more research is needed to further delineate the consequences associated with unnecessary drug use in elderly patients. Health care professionals should be aware of the risks and fully evaluate all medications at each patient visit to prevent polypharmacy from occurring . 

American Pharmaceutical Association, Washington, DC Hajjar ER, Cafiero AC, Hanlon JT (2007) Polypharmacy in elderly patients. Am J Geriatr Pharma-cother 5 345-351... 

The physiological changes and other aspects in the elderly makes this even more complicated. Example of this is decreased stomach acidity decreased motility decreased blood-flow to liver and gastrointestinal tract changed pharmacokinetics and -dynamics polypharmacy swallowing problems bad nutritional status and lack of documentation. 

Sometimes it is argued that it is a good thing that patients do not take the drugs they are prescribed. Polypharmacy, interactions and adverse drug reaction are stated to be the problem. There are at least two major arguments against this. 

Second what is happening when a patient with polypharmacy and low compliance is admitted to hospital-, or to a nursing home care The patient gets all... 

Keywords Drug-related problems Epidemiology Polypharmacy... 

Elderly are more susceptible to adverse effects of drugs due to decreased physiologic reserves, polypharmacy and co-morbidity. Precribers should therefore always consider whether non-pharmacological treatment may be appropriate before prescribing additional drugs to elderly patients. 

There is no universal definition of polypharmacy. One common definition is the use of five or more drugs. This is also the definition that we use in this book. With increasing number of drugs the risk for adverse drug reactions increases. 

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