Avoiding drug reactions: seven steps to writing safe prescriptions

Two-thirds of patients age 65 and older use one or more drugs daily. The number of drugs taken by older patients greatly influences their chances of experiencing a drug reaction. Many patients take their medications incorrectly, and a large number receive prescriptions from more than one physician. The physiologic changes that occur with aging also affect drug absorption, distribution, protein binding, biotransformation, and excretion (pharmacokinetics). Drugs may react with other drugs, with chronic disease, with alcohol, and with nutrients in the patient's diet. By careful prescribing, however, the physician can minimize the potential for ill effects of multiple drug therapies for older patients. Seven prescribing steps are outlined.