How the Effectiveness of Your Medicine Changes with Age

You’ve been taking medication for a chronic condition, but lately, you find that it doesn’t work the same way it did when you first started. Or you suddenly start developing side effects from a medication that you’ve successfully tolerated for years.

What happened? It may be very simple: you’re older. Especially once you turn 65, normal age-related changes in the way your body works can cause medications to be metabolized differently.

The following 5 aging-related changes in your body can affect the way your medications work:

1. Your Kidney Function Declines

Kidney function begins to decrease at around age 40, and that decline continues at the rate of approximately 1% a year. As a result, the medication you take stays in your body longer, and that can lead to an increase in or sudden appearance of side effects.

2. Your Liver Function Declines

The liver also processes medications, and its efficiency also declines as you age. As a result, medication remains in the liver. This increases the risk of side effects, as well as the risk of liver damage.

3. Your Digestive System Slows Down

This means it takes longer for medicines to be absorbed into your system. Moreover, you produce less digestive acid as you get older, which means it takes longer for some drugs to be metabolized and enter your bloodstream. The result? Your medications may become may need more time to take effect, or they may lose effectiveness altogether.

4. Your Proportion of Body Fat Increases

As we age, the amount of muscle in our body decreases — and the amount of fat increases. Even if your weight stays the same, the proportion of it that is fat is likely to be greater than it was when you were younger. As a result, medicines that are fat-soluble, meaning that they dissolve in fat, may be absorbed by the extra fat cells, and remain in your body for longer periods of time. This can increase the effects of the medications, including the side effects.

5. Your Body Becomes Less Hydrated

What about water-soluble medications? Well, your body’s cells lose water as you age. As a result, they are less able to process water-soluble medications. This means that a medication may take longer to be eliminated from the body, increasing its effect.

The result of all these changes is that the risks associated with medications become higher as you age.

The best way to take control is to speak with your doctor about any changes you might notice.

It is also a good idea to schedule a follow-up appointment a few weeks after starting a new medication, so that your doctor can assess how your body is tolerating the new medicine.

At Hamilton Grove Healthcare and Rehabilitation Center, in Hamilton, NJ, our caregivers are trained to keep their eye on the medications our residents take, and to monitor any changes in effects or side effects. It’s just one of the ways we ensure that everyone here can enjoy their best possible life.

Read our reviews on,, and to hear what our residents and their families have to say.

Or better yet, come see for yourself: Contact us to schedule a tour by calling 609-588-5800 or by clicking here.

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