Medications are at the heart of the treatment for nearly every disease we treat in older adults. The U.S. Centers for Disease Control and Prevent (CDC) reports that 85% of people over 60 years old take prescription medications.1 However, there is a delicate balance between the risks and benefits of these medications, especially since our older adults experience more negative effects of medicines compared to other age groups. While they can be extremely effective in controlling diseases, there are 3 major ways that medications can cause problems for our older adults: negative effects of medications, drug interactions, and incorrect doses of medications as kidney function changes. One major focus of your healthcare team is to balance the risks and benefits of the medications based on a personalized treatment plan.
Negative effects of Medications
Negative effects (also called “side effects” or “adverse effects”) of medications are common and specific to the type of medications being administered. In many cases, side effects of medications stem from the way the drug helps in the body. For instance, one type of medication we give for memory impairment increases a molecule in the body called acetylcholine. This molecule helps with memory problems, but also causes the bladder to contract. Therefore, some patients who take the medication for memory have the side effect of urinary urgency. This relationship between how the drugs work and the negative effects of the medications is why we can predict the most common side effects for medications. The physician and pharmacist helping manage your medications should be constantly evaluating these side effects and choosing the safest medications for you personally.
Many medications can interact with each other within the body. This happens in several ways. The medications can interact in the stomach and change how they are absorbed, which can lead to too much or too little drug getting inside the body. They can also interact within the body as they are trying to work, causing one drug to be more effective or less effective. Additionally, medications can interact with each other as the body is trying to eliminate, or metabolize, them. The liver is usually responsible for this process. If the liver is using one process to get rid of a drug but another drug uses the same process, then the second drug may not get removed from the body appropriately and there can be too much drug in the body.
Medication Doses and the Kidneys
Regardless of how the drug gets metabolized/processed by the body, most are eliminated from the body through the kidneys in the urine. As we age, our kidneys’ ability to filter and make urine goes down. Additionally, older adults are at higher risk of having short-term kidney problems due to dehydration, medication effects, or other diseases. There are specific recommendations for how medications should be taken when the kidneys are no longer filtering at full capacity. In nearly all cases, medication doses need to be reduced as we age because of this change in our kidney filtration. Again, your doctor and pharmacist should be monitoring this regularly and may require you to have your blood or urine sampled to keep an eye on how your kidneys are functioning.
Good, But not Perfect
In a perfect world, our medications would be targeted exactly to the disease we want to treat and there would be no side effects. Unfortunately, this is not the case. Medications do many great things, and save thousands of lives every day. But they do require some advanced problem solving by your healthcare team to ensure that you get the best medication for YOU. In doing so, we can maximize the benefits and minimize the negative effects.