What is it?
Pennyroyal essential oil contains chemicals that have various toxic effects in the body.
People use pennyroyal for the common cold, pneumonia, fatigue, ending a pregnancy (abortion), and as an insect repellant, but there is no good scientific evidence to support these uses. It is also unsafe.
How effective is it?
There is interest in using pennyroyal for a number of purposes, but there isn't enough reliable information to say whether it might be helpful.
Is it safe?
When applied to the skin: Pennyroyal essential oil is likely unsafe.
Special precautions & warnings:Pregnancy: It is likely unsafe to take pennyroyal by mouth or apply it to your skin when pregnant. There is some evidence that pennyroyal oil can cause abortions by causing the uterus to contract. But the dose needed in order to cause an abortion could kill the parent or cause life-long kidney and liver damage. Avoid use.
Breast-feeding: It is likely unsafe to take pennyroyal by mouth or apply it to your skin while breast-feeding. Avoid use.
Children: Pennyroyal is likely unsafe when taken by mouth in children. Infants have developed serious liver and nervous system damage, and even death, after taking pennyroyal.
Kidney disease: Pennyroyal essential oil can damage the kidney and make existing kidney disease worse.
Liver disease: Pennyroyal essential oil can cause liver damage and might make existing liver disease worse.
Are there interactions with medications?
- Acetaminophen (Tylenol, others)
- Pennyroyal can cause liver damage. Taking pennyroyal with acetaminophen, which causes a similar type of liver damage, might increase the risk for liver damage.
Are there interactions with herbs and supplements?
- Pennyroyal might reduce how much iron the body absorbs from supplements.
Are there interactions with foods?
- Pennyroyal might reduce how much iron the body absorbs from food.
How is it typically used?
To learn more about how this article was written, please see the Natural Medicines Comprehensive Database methodology.
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