What Medications Cannot Be Taken With Black Cohosh?

October 8, 2025 •

4 min read

In the United States and the United Kingdom, 80% of postmenopausal women report using herbal medicine to manage symptoms [1.8.3]. This guide explores a crucial question for many: What medications cannot be taken with black cohosh to avoid harmful interactions?

Quick Summary

Understand the significant drug interactions with black cohosh. This includes medications that pose a risk of liver damage, hormone therapies, statins, and others.

Key Points

Hepatotoxic Drugs: Do not take black cohosh with other medications that can harm the liver, such as acetaminophen and certain antibiotics, as it increases the risk of liver damage [1.2.3].
Statins: Combining black cohosh with statins like atorvastatin (Lipitor) elevates the risk of liver injury and may alter the medication's effectiveness [1.6.2, 1.6.3].
Hormone Therapies: Black cohosh may interfere with estrogen pills and Hormone Replacement Therapy (HRT) and is not recommended for those with hormone-sensitive cancers [1.4.1, 1.7.1].
Liver Health is Paramount: The primary and most severe interaction risk involves liver damage (hepatotoxicity), with over 80 cases reported globally [1.3.1, 1.3.2].
Blood Thinners: There's a potential interaction with drugs like warfarin and aspirin, which could increase bleeding risk [1.5.1, 1.5.3].
Serotonergic Medications: Combining with certain antidepressants can lead to a dangerous build-up of serotonin, known as serotonin toxicity [1.4.7].
Consult a Professional: Always talk to a doctor or pharmacist before taking black cohosh, especially if you are on any other medication [1.7.1].

Understanding Black Cohosh and Its Uses

Black cohosh (Actaea racemosa) is a popular herbal supplement derived from a plant native to North America [1.3.1]. It is most commonly used to alleviate symptoms associated with menopause, such as hot flashes [1.4.3]. Its traditional use by Native Americans also included treating gynecological disorders, kidney issues, and sore throat [1.3.1]. While many people turn to it for relief, it's crucial to understand that natural does not always mean safe, especially when combined with other medications.

The primary concern surrounding black cohosh is its potential for hepatotoxicity, or liver damage. More than 50 cases of clinically apparent liver injury have been linked to products labeled as black cohosh, with some instances being severe enough to require a liver transplant [1.3.1]. For this reason, regulatory bodies in Australia and Europe mandate warning labels on products containing it [1.3.1, 1.3.7].

The Mechanism of Interaction

Black cohosh can interact with other drugs in several ways:

Liver Metabolism: Many medications are processed by enzymes in the liver. Black cohosh can also affect these enzymes, potentially increasing the risk of liver damage when taken with other drugs that are known to be hard on the liver (hepatotoxic agents) [1.2.3, 1.6.2]. There's also evidence that it can inhibit certain enzymes like CYP2C9, which could increase the concentration of drugs metabolized by this pathway, such as rosuvastatin [1.6.5].
Cell Transporters: Some studies suggest black cohosh can make cell transporters like Organic Anion-Transporting Polypeptides (OATPs) less active. This can decrease the absorption of certain medications, potentially reducing their effectiveness. Drugs affected by this include some statins, fexofenadine (Allegra), and glyburide [1.6.3].
Hormonal Effects: Black cohosh was once thought to have estrogen-like effects. While newer research suggests it may not be a true "herbal estrogen," there is still concern that it could interfere with hormone-sensitive conditions and treatments like Hormone Replacement Therapy (HRT) [1.4.1, 1.7.1]. It might decrease the effects of estrogen pills [1.4.1].
Serotonergic Effects: The supplement may increase levels of serotonin in the brain. Combining it with other serotonergic drugs, such as certain antidepressants, could lead to a dangerous condition called serotonin toxicity [1.4.1, 1.4.7].

Specific Medications You Cannot Take With Black Cohosh

Given the risks, it's essential to avoid black cohosh if you are taking certain medications. Consultation with a healthcare provider is paramount before starting any new supplement.

Hepatotoxic Drugs (Liver-damaging Medications)

The most significant risk is the compounded potential for liver damage. If you take any medication known to be potentially harmful to the liver, you should not take black cohosh [1.2.3].

Common examples include:

Acetaminophen (Tylenol) [1.2.2, 1.2.3]
Statins like atorvastatin (Lipitor), lovastatin (Mevacor), and simvastatin (Zocor) [1.2.3, 1.6.2]
Amiodarone (Cordarone) [1.2.3]
Carbamazepine (Tegretol) [1.2.3]
Methotrexate (Rheumatrex) [1.2.3]
Isoniazid (INH) [1.2.3]
Certain azole antifungal agents like fluconazole (Diflucan) and itraconazole (Sporanox) [1.2.3]
Alcohol should also be limited or avoided as it also puts stress on the liver [1.2.2].

Atorvastatin (Lipitor) and Other Statins

Statins, which are used to lower cholesterol, carry their own risk of liver issues, and this risk is amplified when combined with black cohosh [1.6.2]. The interaction is twofold: the shared risk of hepatotoxicity and the potential for black cohosh to interfere with how statins are absorbed and metabolized [1.6.3, 1.6.6]. This can either reduce the effectiveness of the statin or increase its concentration in the blood, leading to a higher risk of side effects like rhabdomyolysis (muscle breakdown) [1.6.2, 1.6.5].

Hormone Therapies and Hormone-Sensitive Conditions

Due to its potential effects on hormones, black cohosh should be used with caution or avoided by individuals with hormone-sensitive conditions like breast cancer, uterine cancer, endometriosis, or fibroids [1.7.1]. Taking black cohosh alongside estrogen pills or Hormone Replacement Therapy (HRT) might decrease the effectiveness of the estrogen treatment [1.4.1]. Women with a history of breast cancer should consult their physician before using the supplement [1.4.4].

Blood Thinners

WebMD notes a potential interaction with the blood thinner warfarin [1.5.3]. Another source indicates that black cohosh contains salicylic acid, the compound from which aspirin is derived, and advises against its use for anyone taking blood thinners or daily aspirin due to a potential increase in blood-thinning effects [1.5.1].

Cancer Medications

There is some concern that black cohosh might reduce the efficacy of certain chemotherapy drugs, such as cisplatin and tamoxifen [1.7.5, 1.5.4].

Serotonergic Antidepressants

Combining black cohosh with antidepressants that affect serotonin levels can increase the risk of serotonin toxicity, a potentially life-threatening condition. Symptoms can include heart problems, vomiting, and seizures [1.4.1, 1.4.7].

Comparison of Major Drug Interactions


Medication Class	Specific Examples	Nature of Interaction	Risk Level
Hepatotoxic Drugs	Acetaminophen, Methotrexate, Amiodarone, Isoniazid	Increased and cumulative risk of liver damage (hepatotoxicity) [1.2.1, 1.2.3]	High
Statins	Atorvastatin (Lipitor), Simvastatin (Zocor), Rosuvastatin (Crestor)	Increased risk of liver damage and rhabdomyolysis; may decrease statin effectiveness [1.6.2, 1.6.3, 1.6.5]	High
Hormone Therapies	Estrogen pills, HRT	May decrease the effects of estrogen therapy; contraindicated in many hormone-sensitive conditions [1.4.1, 1.7.1]	Moderate
Blood Thinners	Warfarin, Aspirin	May increase the blood-thinning effect and risk of bleeding [1.5.1, 1.5.3]	Moderate
Chemotherapy Drugs	Cisplatin, Tamoxifen	May decrease the effectiveness of the cancer treatment [1.5.4, 1.7.5]	Moderate
Serotonergic Drugs	Certain antidepressants	Increased risk of serotonin toxicity [1.4.1, 1.4.7]	Moderate

Conclusion: Prioritize Safety and Medical Advice

While black cohosh may offer relief for menopausal symptoms, its potential for serious drug interactions—particularly with medications affecting the liver—cannot be overlooked. The link between black cohosh and liver damage is a significant concern, with dozens of cases reported worldwide [1.3.2]. Individuals with liver disease or those taking any medication metabolized by the liver should avoid this supplement [1.7.1]. Furthermore, its effects on hormones and blood coagulation necessitate caution for a wide range of individuals. Always consult with a healthcare professional before combining black cohosh with any prescription or over-the-counter medication to ensure safety and prevent adverse health outcomes.

For more information from an authoritative source, you can visit the National Institutes of Health (NIH) Fact Sheet on Black Cohosh.

Frequently Asked Questions

No, it is not recommended. Both black cohosh and acetaminophen can potentially harm the liver, and taking them together increases the risk of liver damage [1.2.2, 1.2.3].

It may be unsafe. Black cohosh can have serotonergic properties and may interact with certain antidepressants, potentially leading to serotonin toxicity. You should consult your healthcare provider [1.4.1, 1.4.7].

Yes. Black cohosh can interact with statins such as atorvastatin (Lipitor). This combination can increase the risk of liver damage and may also affect how well the statin works [1.6.2, 1.6.3].

Symptoms of liver damage include fatigue, loss of appetite, dark urine, abdominal pain, yellowing of the skin or eyes (jaundice), and pale stools. If you experience these, stop taking black cohosh and see a doctor immediately [1.2.1, 1.3.7].

It is generally advised to avoid black cohosh if you have a history of hormone-sensitive conditions like breast cancer. Its effects on hormones are still not fully understood, and you should speak with your healthcare provider before use [1.4.1, 1.7.1].

There is a potential interaction. Some sources suggest black cohosh may have blood-thinning properties, which could increase the risk of bleeding when taken with anticoagulants like warfarin or aspirin [1.5.1, 1.5.3].

Yes, it might. Taking black cohosh with estrogen pills or other forms of HRT could decrease the effects of the estrogen. Consult your doctor before combining them [1.4.1].