Primary Groups Who Must Avoid Oil of Oregano
While oil of oregano is a popular natural supplement, its high potency makes it unsafe for several specific groups. These contraindications are not minor warnings but critical health precautions based on potential severe interactions and side effects. For these individuals, the risks far outweigh any purported benefits.
Pregnant and Breastfeeding Women Pregnant and breastfeeding women should avoid oil of oregano due to its potential to cause harm. In large, medicinal doses, oregano oil acts as an emmenagogue, which can stimulate uterine blood flow and contractions, potentially leading to a miscarriage. Since the effects on a nursing infant are not well-studied, breastfeeding individuals should also err on the side of caution. The concentrated compounds in the oil can affect both the mother and child, and without sufficient medical research, it is not worth the risk. For these reasons, sticking to food-safe amounts of the fresh or dried herb is the safest approach.
Individuals on Blood Thinners or with Bleeding Disorders Oregano oil can significantly increase the risk of bleeding. It is known to reduce how effectively blood platelets can clump together, which is a crucial part of the clotting process. This effect can be particularly dangerous for individuals with existing bleeding disorders or those taking anticoagulant and antiplatelet medications such as warfarin, aspirin, or clopidogrel. In these cases, the combination can lead to excessive bruising and a heightened risk of serious bleeding. It is highly recommended to stop taking oregano oil at least two weeks before any scheduled surgery.
People with Diabetes Oregano oil has been observed to lower blood sugar levels. For individuals with diabetes, especially those on medications like insulin or oral antidiabetic drugs, this can be extremely hazardous. The combined effect of oregano oil and prescribed medication could cause hypoglycemia (dangerously low blood sugar). Symptoms of hypoglycemia, such as dizziness, fatigue, and confusion, can be severe. Therefore, anyone managing diabetes should avoid oregano oil unless under strict medical supervision and with careful blood sugar monitoring.
Those with Allergies to the Lamiaceae Plant Family Oregano is a member of the Lamiaceae, or mint, family, which also includes basil, sage, lavender, marjoram, and hyssop. If you have a known allergy to any plant in this family, you are at a higher risk of developing an allergic reaction to oregano oil. Symptoms can range from mild skin irritation to more serious respiratory distress. Always perform a patch test when using oregano oil topically and discontinue use immediately if any reaction occurs.
Infants and Children There is insufficient research to determine the safety and appropriate dosage of oregano oil for infants and children. Due to the potent nature of the oil and the lack of established safety guidelines for this population, it is best to avoid its use unless specifically recommended and supervised by a pediatrician.
Medication Interactions to Watch For
In addition to the primary contraindications, oil of oregano can interact negatively with several other substances:
- Diuretics: Oregano has natural diuretic properties. Taking it with diuretic medications can increase their effects, potentially leading to dehydration or electrolyte imbalance.
- Iron, Copper, and Zinc Supplements: Oregano oil can inhibit the absorption of certain minerals, most notably iron. If you are taking supplements for these minerals, you should take the oregano oil at least two hours before or after to minimize interference.
- Herbal Supplements Affecting Blood Clotting: Combining oregano oil with other herbs that also slow blood clotting, such as garlic, ginger, or ginkgo, can amplify the risk of bleeding.
Risks and Side Effects of Overuse
Even for healthy individuals without contraindications, improper use of oil of oregano can lead to unpleasant side effects. Since the product is highly concentrated, overuse is a common issue.
Potential Side Effects:
- Skin Irritation: Applying undiluted oregano essential oil directly to the skin can cause redness, irritation, or burns. It is crucial to always dilute it with a carrier oil like coconut or olive oil before topical application.
- Gastrointestinal Distress: Taken orally in excessive amounts, oregano oil can cause nausea, vomiting, diarrhea, and other stomach problems. Always follow the recommended dosage and consider taking it with food to reduce gastric upset.
- Internal Burns: The highly concentrated nature of pure oregano essential oil makes ingesting it without proper dilution extremely dangerous, as it can cause internal burns. Only consume specific oral supplements or properly diluted drops as directed.
Comparison Table: Oregano Oil Users
| Group | Status | Reason for Caution | Action |
|---|---|---|---|
| Pregnant/Nursing Women | Avoid | Potential for uterine contractions and risks to the infant. | Stick to food-safe amounts of the herb; avoid oil. |
| Bleeding Disorders/Blood Thinners | Avoid | Increases bleeding risk by inhibiting blood clotting. | Stop use at least 2 weeks before surgery; consult doctor. |
| Diabetics on Medication | Avoid | Can cause dangerous drops in blood sugar (hypoglycemia). | Closely monitor blood sugar; consult healthcare provider. |
| Mint Family Allergies | Avoid | High risk of allergic reaction, including skin irritation and respiratory issues. | Test with a patch test; stop immediately if reaction occurs. |
| Infants and Children | Avoid | Safety is not established; potential for adverse effects. | Use only under a pediatrician's direct recommendation. |
| Healthy Adults | Caution | Risks of gastrointestinal issues and skin irritation from overuse or improper dilution. | Follow dosage guidelines; always dilute for topical use. |
Conclusion
While the market for natural supplements often presents products like oil of oregano as universally beneficial, this is a dangerous oversimplification. As a powerful, concentrated substance, oil of oregano has a distinct risk profile. Certain individuals must absolutely avoid it to prevent serious health complications, particularly those who are pregnant, on specific medications like blood thinners or diabetes drugs, or have known allergies to mint-family plants. For everyone else, caution and proper usage—including appropriate dilution and adherence to dosage—are essential. Always consult with a healthcare provider before beginning any new supplement regimen to ensure it is safe for your specific health needs.
For more information on herbal supplements and potential risks, consult the NIH's LiverTox resource on oregano.
