Geriatric considerations - Medications: Nursing

Medication considerations in the geriatric population refers to the fact that, as we age, the body undergoes changes. As a result, medications must be used with caution, taking into account both age-related and client-specific changes.

Alright, now when a medication is administered to the body, the body reacts to that drug in various manners, and the study of these reactions is called pharmacokinetics. Pharmacokinetics includes four main elements: absorption, distribution, metabolism, and elimination. Absorption describes how a medication moves from the site of administration to the blood, whereas distribution is the movement of the medication from the blood to body tissues. Conversely, metabolism deals with the biotransformation of medications, which happens mainly in the liver. On the other hand, elimination studies how the body gets rid of the medication or its metabolites, which typically happens in the kidneys. Now, pharmacodynamics involves how a medication affects the body, including the timing of the medication’s onset, peak effect, and duration, as well as interactions with certain receptors.

Now, aging affects each of these elements differently. For example, the rate of absorption in older clients is slower, due to decreased blood flow to the stomach, slower gastric emptying, and decreased acid production, as well as a decrease in the surface area of the small bowel. This means that medications need more time to reach their peak effect. The bioavailability though, which is the percentage of medication that reaches the blood, doesn’t differ with age. As for distribution, with age, body water, serum albumin, along with lean body mass, tend to decrease, in contrast with fat storage which generally goes up. This causes water-soluble medications to have lower volume of distribution, and fat-soluble medications to have higher volume of distribution, in addition to high proportion of free or active metabolites of the medication. When it comes to metabolism, geriatric clients have decreased hepatic blood flow and size, as well as decreased activity of cytochrome P450 enzymes. These changes impair metabolism of medications in the liver. Elimination is typically also slower in older clients. And that’s mainly due to their reduced kidney size and blood flow to the kidneys, which causes a drop in the glomerular filtration rate, or GFR for short.

Okay, when it comes to pharmacodynamics, age-related changes to receptor sites can result in a loss of receptor sensitivity to certain medications, which can result in a reduced response. On the other hand, due to increased permeability of the blood-brain barrier, elderly clients can experience increased central nervous system effects of some medications, which may result in dizziness, sedation, and confusion.

Now, elderly clients often have one or more chronic disorders, so they may need to take multiple medications. This results in polypharmacy, which is defined as regular use of at least five medications. Use of multiple medications can lead to problems like poor medication adherence and increased risk of harmful interactions between medications, as well as adverse effects, such as weight loss, urinary incontinence, a decline in functional status, cognitive impairment, increased risk of falls, and even increased mortality.

Alright, now to improve the safety of medication administration in older clients, Beers criteria is typically used. This is a tool that was created by the American Geriatrics Society, or AGS for short, and aims at optimizing safe medication use in the geriatric population. Specifically, Beers criteria have been designed to reduce medication-related issues, such as exposure to inappropriate medications, interactions between various medications, and medications that need extra caution in older individuals. The Beers criteria groups medications into three categories: medications to avoid in older clients, medications to avoid in older clients with certain conditions, and medications that should be used with caution in older clients.

Alright, now let’s talk about some medication considerations for geriatric clients. The goal of care is to promote medication safety.

Start by reviewing your client’s current health record including renal and liver function tests. Then carefully reconcile home medications with your client, preferably by having them show you the pill bottles for the medications they take. Remember to ask about medications prescribed from other healthcare providers or following any recent hospitalization. Also review if they are taking any over the counter medications or supplements, because these can have interactions with common medications. Be sure to consult with the pharmacist and healthcare provider to determine if adjustments in the client’s medication should be made or if additional monitoring is needed.