You expect to feel tired if you take sleeping pills. But when other medications make you sleepy, it can interfere with your life.
“Many medicines can have this side effect,” says Barb Hergert, PharmD, a clinical pharmacist in Optum’s Clinical Engagement Services Center.
Among the medications likely to cause drowsiness, antihistamines are among the most common. This includes over-the-counter brands you might be familiar with, including Benadryl and Zyrtec.
Some other medications that might cause sleepiness include:
- antianxiety medications
- antidepressants
- antipsychotic medications
- antiseizure medications
- beta-blockers
- muscle relaxers
- opioids
In some cases, you may not even realize that your medication is responsible for your drowsiness. But knowing more about the medications that cause it and ways to counteract it can help you manage drowsiness while you manage your health.
Why do some medications make you drowsy?
The reason some medications make you sleepy depends on the type of medication. For example, drugs that slow your heart rate, such as benzodiazepines, can have a relaxing or sedative effect on your body, which can lead to drowsiness.
Antihistamines like diphenhydramine (Benadryl) and cetirizine (Zyrtec) that people take for allergies or colds often list drowsiness as a side effect. This could be related to how they work in the brain.
According to Hergert, “Everyone reacts to medicines differently, so it’s hard to generalize. But let’s use beta-blockers as an example. They lower your heart rate, which could leave you feeling a little tired.
Antihistamines, on the other hand, work differently. People with seasonal allergies often take them to block histamine. This is a chemical your body makes, and it’s responsible for allergic reactions such as congestion, sneezing, and itchy eyes.
But histamines also work on the brain. They block receptors that regulate sleep and wakefulness. So when you take an antihistamine to get relief from your allergies, it may also affect your sleep cycle.”
What should I do when I realize that a new medication is making me drowsy?
Hergert says, “If you’re just starting on a medication that’s known to cause drowsiness, avoid doing activities that require alertness — such as driving — until you know how it affects you. Then give it a few weeks. Your body may adjust to the medication, and you’ll start to feel less drowsy.”
What if some time goes by and I still feel drowsy?
According to Hergert, “If you feel you aren’t adjusting to your medication, reach out to your doctor. He or she may be able to recommend ways to reduce or eliminate the drowsiness. For instance, it may be that the dose or the time of day you take the medication should be adjusted.
In some cases, your doctor may recommend a different medication. Just be sure you make this decision with your doctor’s help. You shouldn’t make these kinds of changes on your own.”
What should I do if my antihistamine is making me drowsy?
Antihistamines may be first-generation antihistamines or second-generation ones. First-generation antihistamines are more likely to cross the blood–brain barrier, meaning they directly affect the brain and the central nervous system, making drowsiness more likely.
Hergert says, “Older, first-generation antihistamines are more likely to cause drowsiness. These include diphenhydramine (Benadryl), chlorpheniramine (Chlor-Trimeton), and hydroxyzine (Vistaril).
If you take one of these medications, consider taking it at bedtime. Alternatively, you can talk to your doctor about switching. Newer, second-generation antihistamines are less likely to cause drowsiness. These include fexofenadine (Allegra), loratadine (Claritin), and cetirizine (Zyrtec).”
If you need help covering the cost of medications, the free Optum Perks Discount Card could help you save up to 80% on prescription drugs. Follow the links on drug names for savings on that medication, or search for a specific drug here.
