Acetaminophen is one of the most common painkillers. Many people use it to relieve headaches, fever, or general pain. You might know it by brand names like Panadol or Tylenol. Most of us take it as a pill at home. But in hospitals, it is sometimes given directly into the bloodstream through a method called intravenous delivery.
Doctors choose this method for several reasons. It works faster, allows better control over the amount given, and is helpful for patients who cannot take pills.
However, researchers have found a surprising side effect when acetaminophen is given this way. It can cause a noticeable drop in blood pressure, even in people who are not seriously ill.
In a study, six out of ten very sick patients who received intravenous acetaminophen had lower blood pressure. One-third of them needed medical help because the drop was too much. Despite this, the drug is still widely used because it is generally safe and effective.
To understand why this happens, researchers at the University of Copenhagen, led by Thomas Qvistgaard Jepps, looked deeper. They found that when acetaminophen is given through the veins, it bypasses the liver. This causes the body to produce different chemicals than when the drug is taken as a pill.
These new chemicals affect potassium channels in the blood vessels. Potassium channels help control blood pressure. When these channels are affected, the blood pressure can drop. In tests on rats, the researchers blocked these channels and saw that the drop in blood pressure was reduced.
This discovery is important for hospital staff, especially during times like the COVID-19 pandemic when many patients are treated with intravenous drugs. Knowing this side effect can help doctors manage patients better.
For most people taking acetaminophen by mouth at home, there is no need to worry. If you follow the correct dose, the drug is safe and does not affect blood pressure in the same way.
This study is another example of how a common medicine can behave differently depending on how it is used. It also shows the importance of ongoing research to make sure even well-known drugs are used in the safest way possible.
If you care about blood pressure, please read studies about unhealthy habits that could increase high blood pressure risk, and eating eggs in a healthy diet may reduce risks of diabetes, high blood pressure.
For more information about blood pressure, please see recent studies that early time-restricted eating could help improve blood pressure, and results showing 12 foods that lower blood pressure.
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