Acetaminophen is a common pain medicine that many people take to help with headaches, fevers, or body aches. Most of the time, it’s taken as a pill and is considered safe when used correctly.
But in hospitals, doctors sometimes give this medicine directly into a patient’s vein, which is called intravenous or IV acetaminophen.
This method works faster and is helpful for people who can’t take pills. It also allows doctors to give an exact dose. However, a new study shows that this way of giving acetaminophen might have an unexpected side effect: a drop in blood pressure.
This drop in blood pressure doesn’t just happen in very sick patients—it can happen to anyone who gets the medicine through an IV. Research shows that about six out of ten seriously ill patients had a drop in blood pressure after getting IV acetaminophen, and one-third of them needed medical help to bring their blood pressure back up.
The study was led by Thomas Qvistgaard Jepps and his team at the University of Copenhagen. They wanted to find out why this drop happens.
They discovered that when acetaminophen is given through an IV, it skips the liver, which changes how the body processes it. This change affects something in the body called potassium channels, which help control blood pressure.
In tests with rats, the researchers were able to block these potassium channels and stop the drop in blood pressure. This could lead to new ways to protect patients who need IV pain relief, especially in emergency situations like the COVID-19 pandemic, when this method was used more often.
For most people who take acetaminophen as a pill and follow the correct dose, there’s no need to worry about blood pressure problems. But this study is a good reminder that how we take a medicine can change how it affects our bodies.
Doctors and nurses in hospitals should be aware of this side effect and watch patients closely after giving IV acetaminophen. Knowing about this risk can help them respond quickly if a patient’s blood pressure drops.
This research offers new information that can help improve patient care. It also shows how even common medications can have unexpected effects when used in different ways.
If you care about blood pressure, please read studies about how diets could help lower high blood pressure, and 3 grams of omega-3s a day keep high blood pressure at bay.
For more health information, please see recent studies about how tea and coffee influence your risk of high blood pressure, and results showing this olive oil could reduce blood pressure in healthy people.
The full study is published in the journal Atherosclerosis, Thrombosis, and Vascular Biology.
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