Does peppermint tea interact with any medications?

October 5, 2025 •

4 min read

In 2023, a survey of 300 respondents showed that over 89% consumed herbal tea for health purposes [1.9.1]. But the question remains for many: does peppermint tea interact with any medications? This popular beverage may affect how certain drugs work in the body.

Quick Summary

Peppermint tea may alter how the body absorbs and metabolizes certain drugs. Key interactions can involve medications for blood pressure, diabetes, and those processed by specific liver enzymes [1.2.2].

Key Points

Liver Enzymes: Peppermint can inhibit cytochrome P450 liver enzymes, altering how the body metabolizes many common drugs [1.2.3, 1.3.1].
Cyclosporine Interaction: A significant interaction exists with the immunosuppressant cyclosporine, where peppermint can dangerously increase drug levels in the blood [1.2.2, 1.4.1].
Blood Pressure & Sugar: Peppermint may lower blood pressure and blood sugar, creating a risk of hypotension or hypoglycemia if taken with corresponding medications [1.5.2, 1.6.1].
Iron Absorption: Drinking peppermint tea, especially with meals, can reduce the absorption of non-heme (plant-based) iron by up to 84% [1.7.1, 1.7.2].
Warfarin Caution: A case study reported a potential interaction between high consumption of peppermint tea and the blood thinner warfarin, leading to bleeding complications [1.2.6].
Tea vs. Oil: Peppermint oil is much more concentrated than tea; however, regular, high-volume tea consumption may still pose risks [1.8.3, 1.8.5].
Consult a Professional: Always talk to a doctor or pharmacist before regularly consuming peppermint tea if you are taking any prescription or over-the-counter medications [1.2.1].

The Soothing Sip with a Scientific Caveat

Peppermint tea, brewed from the leaves of the Mentha piperita plant, is a globally popular herbal beverage cherished for its refreshing flavor and potential health benefits, such as aiding digestion [1.2.2]. While the U.S. Food and Drug Administration (FDA) generally recognizes peppermint as safe, its active compounds can influence bodily processes, leading to significant interactions with various medications [1.5.6, 1.2.1]. Understanding these potential interactions is crucial for anyone taking prescription or over-the-counter drugs.

The Core of the Interaction: Cytochrome P450 Enzymes

The primary mechanism through which peppermint affects medications is its influence on the cytochrome P450 (CYP450) system in the liver [1.2.3]. This family of enzymes is responsible for breaking down a vast number of drugs and other substances. Research indicates that peppermint can inhibit or change how quickly these enzymes, specifically isoforms like CYP3A4, CYP1A2, CYP2C9, and CYP2C19, metabolize medications [1.2.3, 1.3.1]. When a drug's metabolism is slowed, it can accumulate in the bloodstream, leading to increased effects and a higher risk of side effects. Conversely, if metabolism is sped up, the drug may be cleared too quickly, reducing its effectiveness [1.2.3].

Specific Medications of Concern

While many interactions are theoretical or based on studies of concentrated peppermint oil rather than tea, caution is warranted with several classes of drugs. The concentration of active compounds like menthol is much lower in tea than in essential oils, but regular, high-volume consumption could still pose a risk [1.8.3, 1.8.5].

Cyclosporine

One of the most well-documented interactions is with cyclosporine (Neoral, Sandimmune), an immunosuppressant medication vital for organ transplant recipients [1.2.1, 1.2.2]. Peppermint may decrease the body's ability to break down cyclosporine, leading to elevated levels of the drug in the blood [1.4.3]. This increases the risk of cyclosporine-related side effects and toxicity. Anyone taking this medication should avoid peppermint products without explicit approval and monitoring from their healthcare provider [1.4.1].

Blood Pressure and Diabetes Medications

Studies suggest that peppermint may have a mild effect of lowering both blood pressure and blood sugar [1.5.2, 1.6.1]. While this can be a benefit for some, it poses a risk for those already taking medications for hypertension or diabetes. The combined effect could lead to hypotension (abnormally low blood pressure) or hypoglycemia (abnormally low blood sugar) [1.5.1, 1.6.4]. Symptoms of hypotension can include dizziness and fainting [1.5.1]. Therefore, individuals on these medications should monitor their levels closely if they choose to drink peppermint tea and consult their doctor [1.5.3, 1.6.1].

Iron Supplements

The phenolic compounds in peppermint tea can significantly interfere with the body's ability to absorb non-heme iron, which is the type of iron found in plant-based foods and supplements [1.7.2]. One study noted that peppermint tea could decrease iron absorption by as much as 84% [1.7.1]. This is a critical consideration for individuals with or at risk for iron-deficiency anemia, including vegetarians, vegans, and menstruating women [1.7.2, 1.7.3]. To mitigate this, it's recommended to consume peppermint tea separately from iron-rich meals or supplements [1.7.2].

Other Potential Interactions

Due to its effect on liver enzymes, peppermint may theoretically interact with a wide range of medications [1.2.3]. General warnings are often issued for:

Stomach acid-reducing drugs: Peppermint may interfere with their action [1.2.5].
Heart condition medications: Similar to blood pressure drugs, there's a potential for additive effects [1.2.1].
Anti-seizure, antibiotic, and antifungal medicines: These can also be metabolized by the CYP450 system, creating a potential for interaction [1.2.1, 1.2.4].
Warfarin: A case report described a patient on warfarin who experienced a highly elevated INR (a measure of blood clotting) and bleeding after drinking large amounts of peppermint tea, suggesting a possible interaction [1.2.6].

Comparison of Potential Peppermint Tea Interactions


Medication/Supplement	Potential Interaction with Peppermint Tea	Mechanism/Concern
Cyclosporine	High Risk: May increase drug levels in the blood [1.4.2].	Inhibition of drug metabolism, leading to potential toxicity [1.4.3].
Blood Pressure Meds	Moderate Risk: May enhance the drug's effect [1.5.2].	Potential for additive effects, causing blood pressure to drop too low (hypotension) [1.5.1].
Diabetes Meds	Moderate Risk: May enhance the drug's effect [1.6.1].	Potential for additive effects, causing blood sugar to drop too low (hypoglycemia) [1.6.4].
Iron Supplements	Moderate Risk: Decreases absorption [1.7.1].	Phenolic compounds in tea bind to non-heme iron, inhibiting its uptake [1.7.2].
Warfarin	Low to Moderate Risk: Potential to increase INR [1.2.6].	A single case report suggests a possible interaction; mechanism is unclear [1.2.6].
CYP450 Substrates	Low to Moderate Risk: Can alter drug metabolism [1.2.3].	Inhibition of liver enzymes (e.g., CYP3A4) can change drug levels in the body [1.3.1].

Conclusion: Prioritize Safety and Professional Advice

While a single cup of peppermint tea is unlikely to cause harm for most people, its potential to interact with medications is real and scientifically plausible, particularly with regular or high consumption. The interactions primarily stem from its ability to affect liver enzymes, potentially lowering blood pressure and blood sugar, and inhibiting iron absorption [1.2.3, 1.5.2, 1.7.1]. The most significant known risk is with the immunosuppressant cyclosporine [1.2.2].

Given these potential risks, the most crucial step is open communication. Before making peppermint tea a regular part of your routine, it is essential to consult with a doctor or pharmacist. They can provide personalized advice based on your specific health conditions and the medications you are taking to ensure your safety and well-being.

For further reading on drug interactions with herbal products, a valuable resource is the National Center for Complementary and Integrative Health (NCCIH).

Frequently Asked Questions

You should be cautious. Peppermint tea may lower blood pressure, and when combined with medication, it could cause your blood pressure to drop too low (hypotension) [1.5.1, 1.5.2]. It is best to consult your healthcare provider for personalized advice.

Yes, this is a significant interaction. Peppermint can increase the levels of cyclosporine in your body, raising the risk of toxicity [1.4.2, 1.4.3]. You should not take peppermint if you are on cyclosporine without consulting your doctor [1.2.2].

Peppermint tea contains compounds that can significantly inhibit the absorption of non-heme iron (from plants and supplements) [1.7.2]. One study showed it can reduce absorption by up to 84% [1.7.1]. It's advisable to drink the tea at least an hour apart from meals or supplements.

It might. Peppermint tea has been shown in some studies to lower blood sugar levels [1.6.1]. Combining it with diabetes medication could increase the risk of hypoglycemia (low blood sugar). Monitor your levels and speak with your doctor [1.6.4].

Yes. Peppermint oil is a much more concentrated form of the plant's active ingredients, like menthol, than peppermint tea [1.8.3, 1.8.5]. While most clinical interaction studies focus on the oil, high or regular consumption of the tea still carries potential risk.

Peppermint can inhibit the activity of the cytochrome P450 enzyme system (including CYP3A4, CYP1A2, and others) in the liver. These enzymes are responsible for metabolizing many drugs, and inhibiting them can cause drug levels to become too high or too low in your body [1.2.3].

Caution is advised. There is a case report of a patient on warfarin who experienced an unstable INR and bleeding after consuming a large amount of peppermint tea [1.2.6]. While this is not definitive proof, it suggests a potential interaction that should be discussed with your doctor.