FACT CHECK: Does consuming grapefruit while taking amlodipine cause cardiac arrest?

In a video circulating on social media, a journalist made some claims about amlodipine, a drug used for regulating high blood pressure.

The drug works by relaxing and widening the blood vessels, thereby lowering blood pressure and making it easier for the heart to pump blood around the body.

In the video, the journalist made several claims, one of them stating that amlodipine interacts with grapefruit and when taken together can cause cardiac arrest. She also asserted that 350,000 Nigerians die annually from drug interactions.

“Amlodipine is a blood pressure drug, and it is commonly used around the world. Here in Nigeria, it’s the most common blood pressure drug used. I’m doing the video to talk about something called drug interactions. There are different types of drug interactions: drug-drug and drug-food. 350,000 Nigerians die every year from drug interactions and their family doesn’t know what killed them. A drug-drug interaction is when one drug collides with another drug,” she said.

“Amlodipine has a drug-food interaction. If you know anyone on amlodipine 10mg or 20mg, tell them not to take grapefruit juice. Grapefruit juice has been seen to cause cardiac arrests and arrhythmia, that’s when the heart is beating fast. It feels like you’re scared but it’s very uncomfortable. 

“In America in 1995, we discovered several people that died of cardiac attacks. When people die, they have to retest the drug. The FDA did that and found that grapefruit was a contraindication of amlodipine. 

“I wrote a letter to Coca-Cola and Chivita, they make two juices that contain grapefruit and people can innocently drink those juices. If you want to drink juices you can drink any brand and flavour you want but do not drink five alive or chivita if you’re on amlodipine.”

The video was initially posted by the blogger in August 2022 and currently has more than 6,000 views on Facebook and over 29,000 views on TikTok. However, the video has continued to make the rounds on Facebook and WhatsApp.

But how accurate is the claim?

DOES AMLODIPINE INTERACT WITH GRAPEFRUIT?

According to Medzino, a US online pharmacy, grapefruit and grapefruit juice can interact with amlodipine. The company said eating grapefruit while taking amlodipine can block the action of CYP3A4, the enzymes that break down the drugs in the body, causing the drug to stay longer in the body.

It said this may allow too much of it to enter the bloodstream. Some side effects mentioned include fatigue, dizziness, low blood pressure, vomiting, headaches, joint pain, and, in the worst case, liver, muscle and kidney damage.

Medzino, however, said consuming grapefruit can affect people differently because everyone has different levels of these enzymes in their body.

The US Food and Drug Administration (FDA) also noted that the degree of drug interaction varies with the individual, drug, and volume of grapefruit consumed.

DOES INTERACTION BETWEEN GRAPEFRUIT AND AMLODIPINE CAUSE CARDIAC ARREST?

Some of the side effects of amlodipine include dizziness. Experts say some of the common side effects are headaches, feeling tired, flushing and swollen ankles. However, they usually improve after a few days.

So consuming large amounts of grapefruit while taking the blood pressure-regulating drug can increase the amount of amlodipine in the body, hence, increasing the gravity of side effects.

Addressing this particular claim, Odili Nonso, pharmacist and CEO of DrugIT, told TheCable that grapefruit has been seen to interact with a number of medications, including amlodipine, and the level of interaction will determine if it increases the concentration of the drug in the body.

“In the case of amlodipine, the concentration is not significant. As much as it may slightly increase the concentration of amlodipine, it is usually not to a worrisome level,” he said.

“Based on standard ratings, that level of interaction is seen as minor. It interacts differently in certain individuals but it is not severe.”

VERDICT

The claim is exaggerated. While amlodipine can interact with grapefruit, it is not likely to cause severe effects such as cardiac arrest or death.