- Olea europae, Oleaceae (family).
- Olive leaves come from the olive tree (Olea europae), a native of the Mediterranean. Although olives and olive oil are used as foods, olive leaf is primarily used medicinally or as a tea.
- Laboratory studies indicate that olive leaf may be beneficial as an antibacterial, antifungal, antiviral, or antioxidant. However, there is insufficient evidence in humans to support the use of olive leaf for any indication.
- In the Middle East, olive leaf tea has been used for centuries to treat sore throat, coughs, fevers, high blood pressure, cystitis (bladder infection), and gout (foot inflammation), and to improve general health. Olive leaf poultices have been applied to the skin to treat dermatological conditions, such as boils, rashes, and warts.
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:
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.
Adults (18 years and older):
- There is no proven safe or effective dose for olive leaf in adults.
Children (younger than 18 years):
- There is no proven safe or effective dose for olive leaf in children.
The below doses are based on scientific research, publications, traditional use, or expert opinion. Many herbs and supplements have not been thoroughly tested, and safety and effectiveness may not be proven. Brands may be made differently, with variable ingredients, even within the same brand. The below doses may not apply to all products. You should read product labels, and discuss doses with a qualified healthcare provider before starting therapy.
- Avoid in individuals with a known allergy or hypersensitivity to olive, olive leaf (Olea europaea), its constituents, or related members of the Oleaceae family.
Side Effects and Warnings
- There are very few reports of olive leaf and its adverse effects. There are currently no high quality studies available on the medicinal applications of olive leaf. Use cautiously in patients taking antiviral medications as olive leaf may have antiviral properties.
Pregnancy and Breastfeeding
- Olive leaf is not recommended in pregnant or breastfeeding women due to a lack of available scientific evidence.
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.
Interactions with Drugs
- Although not well studied in humans, olive leaf water extract may have antibacterial, antioxidant, or antifungal properties. Caution is advised when taking olive leaf and other antifungal, antioxidant, or antibacterial agents due to potential additive effects.
- Based on preliminary study, olive leaf extracts may have antiviral effects, and may aid in inhibiting HIV-1 replication. Caution is advised when using olive leaf with antiviral agents or agents used for HIV.
Interactions with Herbs and Dietary Supplements
- Although not well studied in humans, olive leaf water extract may have antibacterial, antioxidant, or antifungal properties. Caution is advised when taking olive leaf and other antifungal, antioxidant, or antibacterial herbs or supplements due to potential additive effects.
- Taking elderberry extract and olive leaf extract may reduce viral loads. Although the interaction may be a positive one, caution is advised in patients taking elderberry or other herbs with potential antiviral effects, due to additive effects.
Most herbs and supplements have not been thoroughly tested for interactions with other herbs, supplements, drugs, or foods. The interactions listed below are based on reports in scientific publications, laboratory experiments, or traditional use. 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.
- This information is based on a systematic review of scientific literature edited and peer-reviewed by contributors to the Natural Standard Research Collaboration ().
- Konlee M. A new triple combination therapy. Posit.Health News 1998;(No 17):12-14.
- Lee-Huang S, Zhang L, Huang PL, et al. Anti-HIV activity of olive leaf extract (OLE) and modulation of host cell gene expression by HIV-1 infection and OLE treatment. Biochem Biophys Res Commun. 8-8-2003;307(4):1029-1037.
- Markin D, Duek L, Berdicevsky, I. In vitro antimicrobial activity of olive leaves. Mycoses 2003;46(3-4):132-136.
- O’Brien NM, Carpenter R, O’Callaghan YC. Et al. Modulatory effects of resveratrol, citroflavan-3-ol, and plant-derived extracts on oxidative stress in U937 cells. J Med Food 2006;9(2):187-195.
Natural Standard developed the above evidence-based information based on a thorough systematic review of the available scientific articles. For comprehensive information about alternative and complementary therapies on the professional level, go to . Selected references are listed below.