Aging and Medications

ByJ. Mark Ruscin, PharmD, FCCP, BCPS, Southern Illinois University Edwardsville School of Pharmacy;
Sunny A. Linnebur, PharmD, BCPS, BCGP, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of Colorado
Reviewed/Revised Jul 2021 | Modified Aug 2023

Medications, the most common medical intervention, are an important part of medical care for older people. Without medications, many older people would function less well or die at an earlier age.

Did You Know...

  • Up to half of older people do not take drugs as directed by their doctor.

  • Older people are more susceptible to the effects (and side effects) of many drugs.

Older people tend to take more drugs than younger people because they are more likely to have more than one chronic medical disorder, such as high blood pressure, diabetes, or arthritis. Most drugs used by older people for chronic disorders are taken for years. Other drugs may be taken for only a short time to treat such problems as infections, some kinds of pain, and constipation. Almost 90% of older adults regularly take at least 1 prescription drug, almost 80% regularly take at least 2 prescription drugs, and 36% regularly take at least 5 different prescription drugs. When over-the-counter and dietary supplements are included, these rates are even higher. Older people who are frail, hospitalized, or in a nursing home take the most drugs. Nursing home residents are prescribed multiple different drugs to take on a regular basis.

Older people also take many nonprescription (over-the-counter, or OTC) drugs. Many OTC drugs are potentially hazardous for older people (see Precautions With Over-the-Counter Drugs: Older People).

Benefits and Risks of Prescription Drugs

Many of the improvements in the health and function of older people during the past several decades can be attributed to the benefits of drugs.

  • Vaccines help prevent many infectious diseases (such as influenza and pneumonia) that once killed many older people.

  • Antibiotics are often effective in treating serious infections, including pneumonia.

  • Drugs to control high blood pressure (antihypertensives) help prevent strokes and heart attacks.

  • Drugs to control pain and other symptoms enable millions of people with arthritis to continue to function.

However, drugs can have effects that are not intended or desired (side effects). Starting in late middle age, the risk of side effects related to the use of drugs increases. Older people are more than twice as susceptible to the side effects of drugs as younger people. Side effects are also likely to be more severe, affecting quality of life and resulting in visits to the doctor and in hospitalization.

Older people are more susceptible to the side effects of drugs for several reasons:

  • As people age, the total amount of water in the body decreases, and the amount of fat tissue increases. Thus, in older people, drugs that dissolve in water reach higher concentrations because there is less water to dilute them, and drugs that dissolve in fat accumulate more because there is relatively more fat tissue to store them (see Drug Distribution).

  • As people age, the kidneys are less able to excrete drugs into urine, and the liver is less able to break down (metabolize) many drugs (see Drug Metabolism). Thus, drugs are less readily removed from the body (see Drug Elimination).

  • Older people usually take more drugs and have more disorders.

  • People who take more drugs have a higher risk of drug interactions.

  • Fewer studies have been done in older people to help identify appropriate doses of drugs.

  • Older people are more likely to have chronic medical disorders that may be worsened by drugs or that may affect how the drugs work.

Older people are more sensitive to the effects of many drugs. For example, older people tend to become sleepier and are more likely to become confused when using certain antianxiety drugs (see table Drugs Used to Treat Anxiety Disorders) or sleep aids to treat insomnia. Some drugs that lower blood pressure tend to lower blood pressure much more dramatically in older people than in younger people. Larger decreases in blood pressure can lead to side effects such as dizziness, light-headedness, and falls. Older people who have such side effects should discuss them with their doctor.


Many commonly used drugs have anticholinergic effects

Anticholinergic: What Does It Mean?

Anticholinergic effects are caused by drugs that block the action of acetylcholine. Acetylcholine is a chemical messenger (neurotransmitter) released by a nerve cell to transmit a signal to a neighboring nerve cell or a cell in a muscle or gland. Acetylcholine helps cells talk to each other. Acetylcholine helps with memory, learning, and concentration. It also helps control the functioning of the heart, blood vessels, airways, and urinary and digestive organs. Drugs that block the effects of acetylcholine can disrupt the normal functioning of these organs.

Many commonly used drugs have anticholinergic effects. Most of these drugs were not designed to have these unwanted effects. Anticholinergic effects include the following:

  • Confusion

  • Blurred vision

  • Constipation

  • Dry mouth

  • Light-headedness and loss of balance

  • Difficulty urinating

However, anticholinergic drugs can also have useful effects, such as helping control tremors, nausea, or overactive bladder.

Older people are more likely to experience anticholinergic effects because the amount of acetylcholine in the body decreases with age. Consequently, anticholinergic drugs block a higher percentage of acetylcholine, so that the aging body is less able to use what little acetylcholine is present. Also, cells in many parts of the body (such as the digestive tract) have fewer sites where acetylcholine can attach. As a result, doctors usually try to avoid using drugs with anticholinergic effects in older people if possible.

A drug may have a side effect because it interacts with

  • A disorder, symptom, or condition other than the one for which the drug is being taken (drug–disease interaction)

  • Another drug (drug–drug interaction)

  • Food (drug–food interaction)

  • A medicinal herb (drug–medicinal herb interaction)

Because older people tend to have more diseases and take more drugs than younger people, they are more likely to have drug–disease and drug–drug interactions. In many drug-disease interactions, taking a dug can worsen a disorder, symptom, or condition (see table Some Disorders and Symptoms That Can Be Worsened by Drugs in Older People).


Patients, doctors, and pharmacists can take steps to reduce the risk of drug–disease and drug–drug interactions. Because over-the-counter drugs and medicinal herbs can interact with other drugs, people should ask their doctor or pharmacist about combining the use of these drugs with prescription drugs.

Not following a doctor’s directions for taking a drug (called nonadherence) can be risky (see Adherence to Drug Treatment). Older age alone does not make people less likely to take drugs as directed. However, up to half of older people do not take drugs as directed. Not taking a drug, taking too little, or taking too much can cause problems. Taking less of a drug because it has side effects may seem reasonable, but people should talk to a doctor before they make any changes in the way they take a drug.

Maximizing the Benefits and Reducing the Risks of Taking Drugs

Older people and the people who care for them can do many things to maximize the benefits and reduce the risks of taking drugs. Any questions about or problems with a drug should be discussed with a doctor or pharmacist. Taking drugs as instructed and communicating with health care providers is essential for avoiding problems and promoting good health.

Know about the drugs and disorders being treated:

  • Keep a list of all medical problems and drug allergies.

  • Keep a list of all drugs being taken, including over-the-counter drugs and supplements, such as vitamins, minerals, and medicinal herbs.

  • Learn why each drug is taken and what its benefits are supposed to be.

  • Learn what side effects each drug may have and what to do if a side effect occurs.

  • Learn how to take each drug, including what time of day it should be taken, whether it can be taken with food, or taken at the same time as other drugs, and when to stop taking the drug.

  • Learn what to do if a dose is missed.

  • Write down information about how to take the drug or ask the doctor, nurse, or pharmacist to write it down (because such information can easily be forgotten).

Use drugs correctly:

  • Take drugs as instructed.

  • Use memory aids, such as a medication organizer, to take drugs as instructed.

  • Before stopping a drug, consult the doctor about any problems—for example, if side effects occur, if the drug does not seem to work, or if the cost of the drug is burdensome.

  • Discard any unused drug from a previous prescription, unless instructed not to do so by a doctor, nurse, or pharmacist.

  • When discarding a drug, follow the disposal instructions on the label, review the information at the Food and Drug Administration's web site, take drugs to an authorized disposal center (possibly at a pharmacy or local law enforcement site), or mix the drug with kitty litter or coffee grounds, tightly wrap in plastic or a similar material, place in a sealable or watertight container or bag, and discard in the trash.

  • Do not take another person’s drug, even if that person’s problem seems similar.

  • Check the expiration date on drugs, and do not use the drug if it has expired.

Work closely with the doctor and pharmacist:

  • Get all prescriptions from the same pharmacy, preferably one that provides comprehensive services (including checking for possible drug interactions) and that maintains a complete drug profile for each person.

  • Bring all drugs being taken to medical appointments if requested to do so.

  • Periodically discuss the list of drugs being taken and the list of disorders with the doctor, nurse, or pharmacist to make sure the drugs are correct and should be continued. For example, people can test themselves by telling their health care providers how they are supposed to take all drugs and asking whether what they have said is correct.

  • Review the list of drugs with the doctor, nurse, or pharmacist every time a drug is changed (doctors and pharmacists can check for interactions between drugs).

  • Make sure the doctor and pharmacist know about all over-the-counter drugs and supplements being taken, including vitamins, minerals, and medicinal herbs.

  • Consult the doctor before taking any new drugs, including over-the-counter drugs and supplements.

  • Report to the doctor or pharmacist any symptoms that might be related to the use of a drug (such as new or unexpected symptoms).

  • If the schedule of taking drugs is too complex to follow, ask the doctor or pharmacist about simplifying it.

  • If seeing more than one doctor, make sure each doctor knows all the drugs being taken.

  • Ask the pharmacist to print the label in large print, and check to make sure it can be read.

  • Ask the pharmacist to package the drug in containers that are easy to hold and to open.

Remembering to Take Drugs as Prescribed

If older people have memory problems, following a complex schedule is even harder. Such people usually need help, often from family members. The doctor can be asked about simplifying the schedule. Often, doses can be rescheduled to make taking the drugs more convenient or reduce the total number of daily doses. Also, over time, some drugs may not be needed any longer and can be stopped.

The following things can help people remember to take their drugs as prescribed:

  • Memory aids

  • Drug containers

  • Smartphone apps

Memory aids

Memory aids can help older people remember to take their drugs. For example, taking a drug can be associated with a specific daily task, such as eating a meal.

Drug containers

A pharmacist can provide containers that help people take drugs as instructed. Daily doses for 1 week or 2 weeks may be packaged in a plastic pack marked with the days or with the times of the day, so that people can keep track of doses taken by noting the empty spaces. Some pharmacies can package drugs in blister packs, so that the daily dose can be easily removed and kept track of. However, such packaging may cost a little more. Additionally, many pharmacies can adjust refill schedules so that regularly used drugs are picked up on a single day each month. This decreases confusion, helps reduce trips to the pharmacy, and minimizes mistakes filling pill organizers.

More elaborate containers with a computerized reminder system are available. These containers beep, flash, or talk at dosing time.

Smartphone apps (cell phone apps)

Apps that help people manage their drugs can be downloaded to multiple smartphones and tablets. These apps can help older people or their family members remember to take their drugs on time. Many of these apps include reminder alerts, which are sent to the device. Some of these apps may cost money.

More Information

The following English-language resources may be useful. Please note that THE MANUAL is not responsible for the content of these resources.

  1. AARP (American Association of Retired People): Broad range of resources intended to help people choose how they live as they age

  2. Benefits Check Up (The National Council on Aging): Information about and search tools to find benefit programs and resources

  3. National Institute on Aging—Tracking Your Medications: Provides guidance and a worksheet to track and manage drugs

  4. How to Dispose of Unused Medicines from the Food and Drug Administration (FDA): Videos and information on drug-take-back programs and disposal methods for drugs

Drugs Mentioned In This Article
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