What are the side effects of red bush? A complete guide to rooibos tea risks

December 5, 2025 •

4 min read

While generally considered a safe and healthy beverage, with case reports of elevated liver enzymes linked to excessive, long-term consumption of red bush (rooibos) tea. Understanding what are the side effects of red bush tea is essential for informed and responsible intake, especially for those with pre-existing conditions.

Quick Summary

This guide provides a comprehensive overview of the potential risks and side effects associated with red bush tea, detailing rare issues like liver problems, hormonal impacts, and interactions with certain medications.

Key Points

Rare Liver Toxicity: Excessive, long-term consumption of red bush tea has been linked to elevated liver enzymes in rare case reports.
Hormone-Sensitive Caution: Because some compounds mimic estrogen, individuals with hormone-sensitive cancers should be cautious with rooibos tea.
Medication Interactions: Red bush tea can interfere with liver enzymes (CYP), potentially altering the effects of medications like certain statins and chemotherapy drugs.
Moderation is Key: Side effects are rare and primarily associated with very high, chronic intake, so moderate consumption is generally considered safe.
Check with a Doctor: Individuals with pre-existing liver or kidney conditions, or those on regular medication, should consult a healthcare provider before regular rooibos consumption.

A detailed look at red bush tea's potential risks

Red bush, more commonly known as rooibos tea, is a popular herbal beverage celebrated for its sweet, earthy flavor and antioxidant content. Unlike traditional black or green teas, it is naturally caffeine-free and low in tannins. However, the perception that 'natural' automatically means 'without risk' is a misconception. While side effects are rare and generally linked to excessive consumption, certain individuals need to exercise caution. This guide explores the documented risks and circumstances under which they may occur.

Liver concerns from excessive consumption

One of the most significant potential side effects, though rare, is liver toxicity. Several case studies have documented elevated liver enzyme levels in individuals consuming large quantities of rooibos tea over extended periods. In one instance, a patient preparing for surgery was found to have liver disturbances and a low platelet count, which resolved after discontinuing daily, large quantities of the tea. Another case involved a 42-year-old woman with elevated liver enzymes that normalized within a week of stopping her high rooibos intake. For most healthy individuals enjoying rooibos in moderation, this is not a concern, but those with pre-existing liver conditions, such as hepatitis, should consult a healthcare provider.

Potential hormonal and estrogenic effects

Certain compounds in red bush tea can exhibit estrogenic activity, meaning they may mimic the effects of estrogen in the body. This can be a significant concern for individuals with hormone-sensitive conditions. For example, those with a history of hormone-sensitive cancers, like breast cancer, should consult their doctor before regularly consuming rooibos tea. The potential for rooibos to alter hormone levels necessitates careful consideration for specific health situations.

Interactions with medications

For those on prescription medications, rooibos tea has the potential for herb-drug interactions, primarily through its effect on the liver's cytochrome P450 (CYP) enzymes, which are responsible for metabolizing many drugs. In vitro studies have indicated that rooibos extracts can inhibit certain CYP enzymes (like CYP3A4, CYP2C8, and CYP2C9), potentially altering the effectiveness or side effects of co-administered drugs.

Medications that may be affected include:

Certain statins: Specifically, drugs like atorvastatin (Lipitor) may have altered blood levels when combined with rooibos.
High blood pressure medication: Rooibos might affect the activity of ACE inhibitors.
Hypoglycemic drugs: Altered metabolism may impact the efficacy of some diabetes medications.
Chemotherapy drugs: Rooibos has high antioxidant activity, which could interfere with the effectiveness of certain chemotherapeutic agents. The Cancer Association of South Africa advises chemotherapy patients to avoid herbal teas, including rooibos, around the time of treatment.

Kidney concerns and allergic reactions

For most people, rooibos is considered safe for the kidneys, and its low oxalic acid content is often highlighted as beneficial for individuals prone to kidney stones. However, long-term, excessive consumption could potentially lead to kidney issues in predisposed individuals, and caution is advised for those with pre-existing kidney conditions. While rare, allergic reactions to rooibos have also been reported. Symptoms can include skin rashes, itching, or gastrointestinal distress. If an adverse reaction occurs, discontinuing use and seeking medical advice is recommended.

Rooibos tea vs. conventional teas: A comparison of side effect profiles

To better understand the safety profile of red bush tea, it helps to compare it with conventional teas made from the Camellia sinensis plant, such as black and green tea.


Feature	Red Bush Tea (Rooibos)	Conventional Teas (Black/Green)
Caffeine	Naturally caffeine-free, eliminating related side effects like insomnia and jitters.	Contains significant caffeine, which can cause sleep disturbances, anxiety, and heart palpitations.
Tannin Content	Very low in tannins, which minimizes a bitter taste and avoids interference with iron absorption.	High tannin content, which can interfere with the absorption of non-heme iron and can cause stomach upset.
Oxalic Acid	Oxalic acid-free, making it a safe alternative for those with a history of kidney stones.	Can contain oxalic acid, which may contribute to kidney stone formation in susceptible individuals.
Estrogenic Activity	Contains phytoestrogens with potential estrogenic activity, a concern for those with hormone-sensitive conditions.	Generally not known for significant estrogenic activity.
Drug Interactions	Potential interaction with medications metabolized by liver enzymes (CYP) and certain chemotherapy drugs.	High tannin and caffeine content can also cause drug interactions.

Conclusion: A balanced approach to consumption

Red bush tea is largely a safe and beneficial beverage for most people, offering high antioxidant levels and a pleasant taste without the drawbacks of caffeine. The side effects are rare and typically linked to habitual, excessive intake. However, it is crucial to approach its consumption with a clear understanding of the potential risks, particularly for specific health situations. Individuals with liver conditions, hormone-sensitive cancers, or those on certain medications should seek advice from a healthcare professional before incorporating large amounts of rooibos into their diet. By exercising moderation and being aware of potential interactions, most people can continue to enjoy rooibos tea as part of a healthy lifestyle. For more information on complementary and alternative medicine, the Memorial Sloan Kettering Cancer Center website is an excellent resource, especially regarding herb-drug interactions.

Remember, personal health circumstances always dictate how your body will react to any food or beverage. When in doubt, a consultation with a medical expert provides the most reliable guidance. The occasional cup of rooibos is generally a delightful and harmless experience, but chronic, high-volume consumption requires extra prudence.

Frequently Asked Questions

While generally safe for most people, red bush tea may not be suitable for everyone. Individuals with liver conditions, hormone-sensitive cancers, or those taking specific medications should exercise caution and consult a healthcare professional.

Yes, excessive consumption of red bush tea over a long period can potentially lead to rare side effects, including liver enzyme elevation. Moderation is key to avoiding issues.

In very rare cases, excessive, long-term consumption of red bush tea has been associated with liver toxicity and elevated liver enzymes. These effects have been documented to reverse upon discontinuation of the tea.

Rooibos tea is naturally caffeine-free and often recommended during pregnancy. However, any herbal consumption during pregnancy should be discussed with a doctor to ensure safety for both mother and baby.

Red bush tea can potentially interact with medications metabolized by the liver's CYP enzymes, such as certain statins (like atorvastatin), ACE inhibitors for blood pressure, and specific chemotherapy drugs. Consult a doctor about potential interactions.

Some compounds in rooibos tea may mimic estrogen in the body. This is a potential concern for individuals with hormone-sensitive conditions, so it is advisable to consult a healthcare provider.

Red bush tea is oxalic acid-free and often considered a good alternative for those at risk of kidney stones. However, individuals with pre-existing kidney disease should consult their doctor, as excessive intake may pose a risk.