A study has raised important questions about the safety of a widely used medicine for high blood pressure.
Researchers found that a high dose of the drug nifedipine may increase the risk of sudden cardiac arrest, a life-threatening condition in which the heart suddenly stops beating.
High blood pressure, also called hypertension, affects millions of people around the world. If left untreated, it can damage blood vessels and increase the risk of heart attacks, strokes, kidney disease, and heart failure. Because of this, doctors often prescribe medicines to help lower blood pressure and reduce strain on the heart.
Nifedipine is one of the medicines commonly used for this purpose. It belongs to a group of drugs called calcium channel blockers.
These medicines help relax and widen blood vessels, making it easier for blood to flow through the body. Nifedipine is also used to treat chest pain, known as angina, which happens when the heart does not get enough oxygen-rich blood.
Another similar drug called amlodipine is also widely prescribed for high blood pressure and chest pain. Both medicines have been used for many years and are generally considered effective and safe. However, the new study suggests that high doses of nifedipine may carry risks that were not fully understood before.
The study was carried out by researchers from the European Sudden Cardiac Arrest Network. They focused on sudden cardiac arrest, which is one of the leading causes of death worldwide.
Sudden cardiac arrest happens when the heart suddenly stops pumping blood properly because of a dangerous electrical problem in the heart.
When this occurs, blood flow to the brain and other organs stops immediately. A person may collapse, lose consciousness, and stop breathing within seconds. Without urgent treatment, sudden cardiac arrest can quickly lead to death.
In Europe, sudden cardiac arrest is responsible for about half of all heart-related deaths and around one in five natural deaths. Despite how serious the condition is, it can be difficult to study because it happens suddenly and often without warning.
To investigate whether blood pressure medicines might affect the risk of sudden cardiac arrest, the researchers studied medical records from more than 2,500 people in the Netherlands who experienced sudden cardiac arrest.
They compared these patients with more than 10,000 healthy people who did not have the condition.
The researchers found that people taking a high dose of nifedipine, specifically 60 milligrams per day, had a greater risk of sudden cardiac arrest. In contrast, people taking amlodipine did not show the same increased risk.
To confirm their findings, the scientists repeated the analysis using medical records from Denmark. This second investigation included more than 8,000 patients and over 40,000 healthy comparison participants.
Once again, the same pattern appeared. High-dose nifedipine was linked to a higher risk of sudden cardiac arrest, while amlodipine was not.
The findings surprised many researchers because nifedipine has been prescribed for decades. One reason the risk may not have been noticed earlier is that sudden cardiac arrest is difficult to predict and study. The event happens very quickly, and it is often hard to determine exactly what triggered it.
Although the results are concerning, the researchers emphasized that more studies are needed before drawing final conclusions. They do not recommend that people suddenly stop taking nifedipine on their own. Instead, they encourage patients to speak with their doctors about any concerns.
Doctors may need to be more cautious when prescribing high doses of nifedipine, especially for patients who already have heart disease or other cardiovascular risks. In some cases, lower doses or alternative medicines may be safer options.
The study also highlights the importance of paying attention to warning signs that may suggest heart trouble. Symptoms such as chest pain, shortness of breath, dizziness, nausea, or unusual weakness should always be discussed with a healthcare professional.
In addition to medication, lifestyle choices play a major role in heart health and reducing the risk of sudden cardiac arrest. Eating a balanced diet, exercising regularly, maintaining a healthy weight, avoiding smoking, and limiting alcohol intake can all help protect the heart.
Regular health check-ups are also important because high blood pressure often develops without obvious symptoms. Many people may not realize their blood pressure is dangerously high until serious complications occur.
For people at very high risk of sudden cardiac arrest, doctors may sometimes recommend an implantable cardioverter defibrillator, also called an ICD.
This small device is placed inside the body and continuously monitors the heart’s rhythm. If the heart suddenly stops or develops a dangerous rhythm, the device can deliver an electric shock to restore normal beating.
Learning CPR, or cardiopulmonary resuscitation, can also save lives during emergencies. CPR helps keep blood flowing to the brain and body until medical professionals arrive.
The new study serves as a reminder that even long-established medicines should continue to be carefully studied. While nifedipine remains helpful for many patients, understanding possible risks is important for making treatments as safe as possible.
Researchers hope future studies will provide clearer answers and help doctors make better decisions for patients with high blood pressure and heart disease.
If you care about heart disease, please read studies that herbal supplements could harm your heart rhythm, and how eating eggs can help reduce heart disease risk.
For more health information, please see recent studies that apple juice could benefit your heart health, and results showing yogurt may help lower the death risks in heart disease.
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