Note: Cajeput oil should not be confused with tea tree oil, although the plants are part of the same genus. According to the U.S. Department of Agriculture, Melaleuca leucadendron and Melaleuca quinquenervia refer to the same plant and this monograph may use these terms interchangeably.
According to the U.S. Department of Agriculture, Melaleuca leucadendron and Melaleuca quinquenervia refer to the same plant.
Cajeput (Melaleuca quinquenervia leucadendron, Melaleuca leucadendron) is a tree native to Australia. Cajeput oil is extracted from the leaves and twigs of the plant. Cajeput leaves may be useful for high blood pressure, herpes simplex, and Helicobacter pylori inhibition. They may also have hypoglycemic effects and may be able to lower blood sugar levels. However, currently there is not enough scientific evidence in humans to support the use of cajeput oil for any indication.
These uses have been tested in humans or animals. Safety and effectiveness have not always been proven. Some of these conditions are potentially serious, and should be evaluated by a qualified healthcare provider.
* Key to grades
A: Strong scientific evidence for this use B: Good scientific evidence for this use C: Unclear scientific evidence for this use D: Fair scientific evidence for this use (it may not work) F: Strong scientific evidence against this use (it likley does not work)
Tradition / Theory
The below uses are based on tradition, scientific theories, or limited research. They often have not been thoroughly tested in humans, and safety and effectiveness have not always been proven. Some of these conditions are potentially serious, and should be evaluated by a qualified healthcare provider. There may be other proposed uses that are not listed below.
The U.S. Food and Drug Administration does not strictly regulate herbs and supplements. There is no guarantee of strength, purity or safety of products, and effects may vary. You should always read product labels. If you have a medical condition, or are taking other drugs, herbs, or supplements, you should speak with a qualified healthcare provider before starting a new therapy. Consult a healthcare provider immediately if you experience side effects.
Avoid in individuals with a known allergy or hypersensitivity to cajeput. Cajeput pollen is a known allergen and may cause positive skin test reactions. In addition, there is a high cross-sensitivity between cajeput, Paspalum notatum, and Callistemon citrinis pollen.
Side Effects and Warnings
There are very few reported adverse effects associated with cajeput. Nonetheless, use cautiously in patients with diabetes, hypoglycemia (low blood sugar), or high or low blood pressure. Leaves harvested from certain areas of the world may contain carcinogenic (cancer-causing) chemicals.
Pregnancy and Breastfeeding
Cajeput oil is not recommended in pregnant or breastfeeding women due to a lack of available scientific evidence.
In theory, cajeput oil may intensify local anesthetic power when combined with other anesthetics.
Although not well studied in humans, cajeput may have potential interactions with antibiotics, antihistamines, antioxidants, or mosquito repellent agents. Consult a qualified healthcare professional, including a pharmacist, to check for interactions.
Cajeput oil may lower blood sugar levels. Caution is advised in patients with diabetes or hypoglycemia (low blood sugar) and in those taking drugs that affect blood sugar. Serum glucose levels may need to be monitored by a qualified healthcare professional, including a pharmacist, and medication adjustments may be necessary.
Cajeput may inhibit the growth of Helicobacter pylori. Use cautiously with ulcer medications. Cajeput fruit may also inhibit herpes simplex I and there is a possible interaction when taking in combination with other antiviral agents. In addition, early evidence suggests that cajeput leaves may alter blood pressure. Use cautiously in patients taking blood pressure medications.
Cajeput may interfere with the way the body processes certain drugs using the liver's "cytochrome P450" enzyme system. As a result, the levels of these drugs may be increased in the blood and may cause increased effects or potentially serious adverse reactions. Patients using any medications should check the package insert and speak with a qualified healthcare professional, including a pharmacist, about possible interactions.
Interactions with Herbs and Dietary Supplements
In theory, cajeput oil may intensify local anesthetic power when combined with other anesthetic herbs or supplements.
Although not well studied in humans, cajeput may have potential interactions with antibiotics, antihistamines, antioxidants, or mosquito repellent herbs or supplements. Consult a qualified healthcare professional, including a pharmacist, to check for interactions.
Cajeput oil may lower blood sugar levels. Caution is advised when using herbs or supplements that may also lower blood sugar. Blood glucose levels may require monitoring and doses may need adjustment.
Cajeput may inhibit the growth of Helicobacter pylori. Use cautiously with herbs and supplements used to manage ulcers. Cajeput fruit may also inhibit herpes simplex I and an interaction is possible when taking in combination with other antiviral herbs and supplements. In addition, early evidence suggests that cajeput leaves may alter blood pressure. Use cautiously in patients taking blood pressure-altering herbs and supplements.
Cajeput may interfere with the way the body processes certain herbs or supplements using the liver's "cytochrome P450" enzyme system. As a result, the levels of other herbs or supplements may become too high in the blood. It may also alter the effects that other herbs or supplements possibly have on the P450 system.
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The information in this monograph is intended for informational purposes only, and is meant to help users better understand health concerns. Information is based on review of scientific research data, historical practice patterns, and clinical experience. This information should not be interpreted as specific medical advice. Users should consult with a qualified healthcare provider for specific questions regarding therapies, diagnosis and/or health conditions, prior to making therapeutic decisions.