Hibiscus Tea Side Effects: What You Need to Know

Hibiscus tea is a tart, cranberry-flavored herbal infusion made from dried hibiscus petals. It's rich in antioxidants, but it isn't risk-free for everyone, especially people on certain medications or who are pregnant.

What's in Hibiscus Tea

Hibiscus tea's deep red color comes from anthocyanins, antioxidant pigments also found in other red and purple produce. It also contains organic acids like citric and malic acid, which give it its tart flavor and a mild diuretic effect, along with some vitamin C.

Potential Side Effects

Digestive Upset

Some people experience stomach cramps or mild diarrhea, particularly when drinking hibiscus tea in large amounts or on an empty stomach. Drinking it with food and starting with a smaller serving can help.

Low Blood Pressure

NCCIH notes that hibiscus may modestly reduce blood pressure in people with hypertension, though the evidence is limited and the effect is small — nowhere near as strong as a prescription medication. That's a benefit for some people, but it can cause dizziness or lightheadedness in those who already have low blood pressure.

Allergic Reactions

Allergic reactions are uncommon but possible, with symptoms like hives, itching, swelling or difficulty breathing. Seek medical attention right away if you notice these symptoms after drinking hibiscus tea.

Skin Irritation

Rarely, direct skin contact with hibiscus tea or petals can cause redness or itching in sensitive individuals.

Medication Interactions

Hibiscus tea's interaction with blood pressure medication is more complicated than simply "adding up" two blood-pressure-lowering effects. A pharmacokinetic study in rats found that hibiscus extract significantly reduced the absorption of captopril, an ACE-inhibitor blood pressure drug — the researchers concluded regular hibiscus tea should be avoided with captopril specifically, since it could make the medication less effective rather than more. Other blood pressure drugs may interact differently. It may also interact with certain diabetes medications, since some research suggests hibiscus can affect blood sugar. Talk to your doctor before drinking hibiscus tea regularly if you take medication for blood pressure, diabetes, or other prescription drugs, and don't assume it's safe to substitute tea for a dose you've missed.

Hibiscus Tea and Pregnancy

Pregnant women are generally advised to avoid hibiscus tea. It's traditionally used as an emmenagogue (a substance believed to stimulate menstrual flow), and there isn't enough human safety data to recommend it during pregnancy. Talk to your doctor before drinking hibiscus tea if you're pregnant or breastfeeding.

Who Should Be Cautious

• People taking blood pressure or diabetes medication
• Pregnant or breastfeeding women
• People with a known allergy to hibiscus or related plants
• Anyone with chronically low blood pressure

FAQ

What are the side effects of hibiscus tea?

The most commonly reported effects are digestive upset, lowered blood pressure and, rarely, allergic reactions. Most people can drink it without issue in moderate amounts.

Can hibiscus tea interact with medications?

Yes. It may interact with blood pressure and diabetes medications in particular. Check with a healthcare provider before drinking it regularly if you take either.

Is hibiscus tea safe during pregnancy?

It's generally not recommended during pregnancy due to limited safety data and a possible uterine-stimulant effect. Talk to your doctor first.

How much hibiscus tea is safe to drink per day?

Most healthy adults tolerate 2–3 cups a day without issue, but start with less if you're new to it, and check with a doctor if you're on medication.

The Bottom Line

Hibiscus tea's antioxidants and mild blood-pressure-lowering effect make it a popular choice, but it's not for everyone. If you're pregnant, on blood pressure or diabetes medication, or prone to low blood pressure, talk to a doctor before adding it to your routine. For more, see our guides to teas for energy and focus, teas for bloating and indigestion and peppermint tea before bed.