Chapter 35 Safe Medication Use

Drugs Commonly Used by Older Adults Cardiovascular agents Antihypertensives Analgesics Antiarthritic agents Sedatives Tranquilizers Laxatives Antacids

Pharmacokinetics and Pharmacodynamics Pharmacokinetics –The absorption, distribution, metabolism, and excretion of drugs Pharmacodynamics –The biologic and therapeutic effects of drugs at the site of action or on the target organ Drugs behave differently in older adults. Careful dosage adjustment and monitoring are needed.

Factors Altering the Absorption of Drugs Age-related changes Route of administration Concentration and solubility of drug Diseases and symptoms

Measures to Maximize the Absorption of Drugs Encourage Exercise. Stimulate circulation and increase blood flow at the absorption site. Prevent fluid volume deficit, hypothermia, and hypotension. Avoid preparations that neutralize gastric secretions if a low gastric pH is required for drug absorption.

Measures to Maximize the Absorption of Drugs (cont.) Monitor drug–drug and drug–food interactions. Monitor drug-herb interactions. Use the most effective administration.

Drugs Having Increased Biological Half- Life Antibiotics Barbiturates Cimetidine Digoxin Salicylate

Conditions That Decrease Metabolism of Drugs Dehydration Hyperthermia Immobility Liver disease

Risk of Adverse Reactions in Elders Symptoms can appear differently in older persons. A prolonged time may be required for an adverse reaction to become apparent. Adverse reactions can be demonstrated after a drug has been discontinued. Adverse reactions can develop to drugs that have been used for a long period without problems.

Questions Nurses Should Ask About Patient Medications Why is the drug ordered? Is the smallest possible dosage ordered? Is the patient allergic to the drug? Can this drug interact with other drugs, herbs, or nutritional supplements that are being used? Are there any special instructions accompanying the drug’s administration? Is the most effective route of administration being used?

Precautions in Drug Administration Do not crush enteric coated tablets. Assure suppositories have been melted, not expelled. Avoid cardiac overload from too rapid IV administration.

Older Adult’s Response to Drugs Increased myocardial sensitivity to anesthesias Increased central nervous system receptor sensitivity to narcotics, alcohol, and bromides

Risk Factors for Medication Errors Multiple medications Cognitive impairment Visual and hearing deficits Arthritic or weak hands History of noncompliance with medical care Lack of knowledge about medications Limited finances

Risk Factors for Medication Errors (cont.) Illiteracy Lack of support system History of inappropriate self-medication Expired or borrowed medications in the home

Alternatives to Medications Lifestyle changes Diet modifications Regular exercise Effective stress management techniques Regular schedules for sleep, rest, and elimination Alternative therapies

Source Eliopoulos, C. (2005). Gerontological Nursing, (6 th ed.). Philadelphia: Lippincott, Williams & Wilkins (ISBN ).