Acetaminophen is a well-known pain reliever that many people use to treat headaches, fevers, and other common problems. Most of the time, people take it as a pill, and it’s considered safe when used as directed.
In hospitals, however, acetaminophen is sometimes given directly into a patient’s vein. This method, called intravenous (IV) delivery, allows the drug to work quickly, ensures a precise dose, and is helpful for patients who can’t swallow pills.
But a new study has found a surprising side effect of using acetaminophen this way—it can cause a big drop in blood pressure. This doesn’t just happen in very sick patients. It can happen to anyone receiving the drug through an IV.
Research shows that about 60% of critically ill patients who received IV acetaminophen had a drop in blood pressure. In about one-third of these cases, doctors had to step in and treat the problem.
The study was led by Thomas Qvistgaard Jepps and his team at the University of Copenhagen. They looked into why this drop happens. They found that when acetaminophen is given through an IV, it skips the liver, which changes how the body reacts. This change affects potassium channels, which help control blood pressure.
In lab tests with rats, the team blocked these potassium channels and were able to stop the blood pressure drop. This discovery could help hospitals find better ways to manage IV pain relief, especially during emergencies like the COVID-19 pandemic, when IV acetaminophen was used more often.
For most people taking acetaminophen by mouth at home, this blood pressure issue is not a concern. The risk appears only with the IV method used in hospitals.
Still, this study is an important reminder that how a drug is given can change how it works in the body. It also shows the need for careful monitoring in hospital settings to catch any problems early.
This research could help improve care for patients and lead to safer ways to use IV medications. The full findings are published in the journal Atherosclerosis, Thrombosis, and Vascular Biology.
If you care about high blood pressure, please read studies that drinking tea could help lower blood pressure, and early time-restricted eating could help improve blood pressure.
For more health information, please see recent studies about added sugar in your diet linked to higher blood pressure, and results showing vitamin D could improve blood pressure in people with diabetes.
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