Acetaminophen is one of the most common painkillers. Many people take it for headaches, fevers, or minor aches, and it’s generally considered safe.
Most of the time, it comes in the form of tablets or capsules that you swallow. But in hospitals, doctors sometimes give it through an IV, which means it goes directly into the bloodstream.
This method has some benefits. IV acetaminophen works faster, which is helpful for patients who need quick pain relief.
Doctors can also control the dose more precisely, making sure patients get the right amount. It’s also useful for people who can’t swallow pills due to surgery or medical conditions.
However, researchers have discovered something surprising about IV acetaminophen—it can cause a sudden drop in blood pressure. This happens even in patients who are not seriously ill.
In hospitals, about six out of ten critically ill patients who received IV acetaminophen experienced a drop in blood pressure. For some, the drop was serious enough that they needed extra medical help.
Even with this side effect, IV acetaminophen is still widely used because it remains an effective pain reliever. But scientists wanted to understand why it affects blood pressure in this way.
A research team, led by Thomas Qvistgaard Jepps from the University of Copenhagen, studied this issue. They found that the way acetaminophen moves through the body changes depending on how it is taken.
When you swallow acetaminophen, it first passes through the liver before entering the bloodstream. In the liver, the drug breaks down into different compounds. But when acetaminophen is given through an IV, it skips the liver and goes straight into the blood.
This difference leads to chemical changes in the body. Some of the compounds produced from IV acetaminophen interact with potassium channels, which help regulate blood pressure. When these channels are affected, blood pressure can drop.
To test this idea, researchers conducted experiments on rats. They blocked the potassium channels that reacted with the IV acetaminophen compounds. As a result, the rats’ blood pressure remained stable, suggesting that these channels play a key role in the blood pressure drop.
These findings could help doctors find ways to prevent this side effect in the future. If medical teams can adjust treatments, they may be able to keep blood pressure stable while still using IV acetaminophen for pain relief.
This research is especially useful for hospitals, where many patients rely on IV pain medication. Understanding this effect allows doctors and nurses to be more careful when giving IV acetaminophen, especially to patients who already have low blood pressure or are at risk for sudden drops.
For people who take acetaminophen by mouth, there is no need to worry. This side effect only happens when the drug is given through an IV. If you follow the recommended dosage at home, you are not at risk for these blood pressure changes.
This study adds to our understanding of how common medications can act differently depending on how they are taken. It also shows why it’s important for healthcare providers to know about these effects so they can give patients the safest treatment possible.
If you care about blood pressure, please read studies that black licorice could cause dangerous high blood pressure, and this common plant nutrient could help reduce high blood pressure.
For more information about blood pressure, please see recent studies about how coffee influence your risk of high blood pressure, and results showing this olive oil could reduce blood pressure in healthy people.
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