6 Drinks That Can Be Dangerous To Mix With Blood Pressure Medications

If you are taking blood pressure medications, such as ACE inhibitors or beta blockers, you may need to avoid certain things, including certain drinks. Indeed, certain drinks can interfere with the way medications work or trigger unwanted side effects. Here are six drinks to ask your doctor about.

Perhaps the most well-known interaction is with grapefruit juice. According to Sabrina Islam, MD, MPH, a cardiologist at Temple Health and associate professor of medicine at the Lewis Katz School of Medicine at Temple University, the drink inhibits an important enzyme called CYP3A4, which helps metabolize and break down many blood pressure medications.

“Drinking excessive amounts of grapefruit juice can, in turn, lead to increased levels of these medications in the blood, which can cause episodes of low blood pressure,” Islam said.

Other fruit juices, including those from apple and citrus fruits like orange, can also affect how your body absorbs and processes certain blood pressure medications, said David Maron, MD, a cardiologist at Stanford Medicine’s Preventative Cardiology Clinic.

Alcohol can enhance the effects of some blood pressure medications, including nondihydropyridine calcium channel blockers, alpha blockers and beta blockers, and can cause significant drops in blood pressure, Islam said.

Alcohol can also worsen the side effects of these medications, including dizziness, lightheadedness, fainting, and changes in heart rate.

Additionally, alcohol itself can raise your blood pressure, negating the benefits of your medications. A little more than two drinks for men or more than one for women may be enough to produce this effect, Maron said.

Caffeine may decrease the effectiveness of blood pressure medications. Research shows that beta blockers and diuretics don’t work as well when caffeine enters the mix.

Maron recommends limiting caffeine intake to less than 400 milligrams (mg) per day, or about the amount in three cups of coffee. For reference, a cup of tea typically contains 35 mg of caffeine, while some energy drinks contain up to 250 mg per serving.

Even in small quantities, licorice tea and drinks containing glycyrrhizin—a tasty chemical found in licorice root—can significantly raise blood pressure and counteract the effects of blood pressure medications.

This happens because glycyrrhizin inhibits a kidney enzyme that normally converts active cortisol into its inactive form, cortisone, Maron explained. As a result, cortisol can build up in the body. “High cortisol levels lead to sodium retention, potassium loss, increased blood volume and high blood pressure,” he said.

Many herbal products can change the way your body processes, absorbs, or eliminates blood pressure medications.

For example, St. John’s wort may interfere with the way medications are metabolized in the liver, while ginseng and ephedra may increase your heart rate and blood pressure, according to Harlan Krumholz, MD, SM, a cardiologist at Yale Medicine.

“These interactions may lessen the effect of the drug or cause side effects such as dizziness, low potassium or abnormal heart rhythms,” he said.

In addition to St. John’s wort, ginseng, and ephedra, Kumbolz recommends avoiding yohimbine and green tea extract in high doses.

Some commercial vegetable juices can increase sodium levels and cause the body to retain fluids. This buildup can strain blood vessels and directly increase blood pressure, Krumholz said. As a result, vegetable juices high in sodium may reduce the benefits conferred by medications such as diuretics, ACE inhibitors, and angiotensin receptor blockers (ARBs).

When this happens, “people may experience swelling, higher blood pressure or reduced effectiveness of medications they are prescribed,” Krumholz said.

Recommendations may vary depending on your individual blood pressure, underlying health conditions, and specific medications you are taking. If you are unsure whether a drink might interfere with your treatment, it is best to speak to a healthcare professional.

“A doctor or pharmacist can help tailor advice and ensure safe choices, because what is risky for one person may be acceptable for another,” Krumholz said.