- Ash wood dust, flavonoids, Fraxini cortex, Fraxinus americana, Fraxinus elatior, Fraxinus excelsior, Fraxinus excelsior L., Fraxinus ornus L., hydroxycoumarins, Oleaceae (family), phenylethanoids, secoiridoid glucosides, white ash.
- Combination product (examples): PhytodolorÂ® (aspen, ash, goldenrod), Rebixiao granule (RBXG) (ash bark, Smilax glabra rhizome).
- Note: This monograph does not include other unrelated species with the common name ash, such as Mountain ash (Sorbus spp.) or Prickly ash (Zanthoxylum spp.).
- Ash has been used since the time of the Native Americans and the early settlers of the Americas. The Native Americans supposedly showed the medicinal properties of nearly every portion of the tree to the settlers. Traditionally, ash has been used to treat external cancerous growths, itching, parasitic worms, and fever. It has also been used as an antiseptic, diuretic, aphrodisiac, and appetite stimulant.
- Today, ash is still used for many conditions, including gouty arthritis, inflammation and pain. It may also be used as a general antimicrobial. It is commonly used in Europe in a variety of combination products. However, little human evidence exists, and only a few scientific studies have been carried out to support any of these claims.
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 (over 18 years old)
- There is no proven safe or effective dose for ash in adults.
Children (under 18 years old)
- There is no proven safe or effective dose for ash 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 to ash (Fraxinus species), its constituents, or to members of the Oleaceae family.
- Exposure to ash wood dust in a work environment may cause effects in individuals with sensitive airways.
- Pollens from Fraxinus spp. may be some of the most commonly inhaled aeroallergens, which change with the season and are usually found during rainy or wet seasons.
- Ash pollen may have allergic cross-reactivities with pollen from the Fagales order (birch, alder, hazel, hornbeam, oak, and chestnut), Scrophulariales order (olive, ash, plantain, privet, and lilac), Coniferales order (cedar, cypress, and pine), and fruits and vegetables. There may also be cross-reactivity with M. annua (annual mercury), Olea europaea (olive), Fraxinus elatior (ash), Ricinus communis (castor bean), Salsola kali (Russian thistle, tumbleweed), Parietaria judaica (spreading pellitory), and Artemisia vulgaris (mugwort, common wormwood).
Side Effects and Warnings
- Documentation of severe adverse effects other than allergic responses is lacking.
- Use cautiously in patients sensitive to blood thinners.
- Use cautiously in patients at risk for low levels of uric acid in the blood (hypouricemia), hyperthyroidism, inflamed kidneys (nephritis), multiple sclerosis, and Fanconi Syndrome (defective renal tubes) since ash may lower blood uric acid concentrations.
- Avoid in patients with a weak immune system since ash may alter how the immune system functions.
Pregnancy & Breastfeeding
- Use of ash or combination products containing ash is not recommended in pregnant or breastfeeding women due to a lack of available 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
- Ash may reduce blood uric acid concentrations and is not recommended for patients taking allopurinol or other drugs that lower uric acid levels.
- Ash may increase the effect of pain relievers.
- Ash may interfere with how antibiotics work in the body and are not recommended for patients undergoing antibiotic therapy.
- Ash may increase the risk of bleeding when taken with drugs that increase the risk of bleeding. Some examples include aspirin, anticoagulants (“blood thinners”) such as warfarin (CoumadinÂ®) or heparin, anti-platelet drugs such as clopidogrel (PlavixÂ®), and non-steroidal anti-inflammatory drugs such as ibuprofen (MotrinÂ®, AdvilÂ®) or naproxen (NaprosynÂ®, AleveÂ®).
- Ash may increase the effect of anti-inflammatory drugs.
- Ash bark, leaves, and flowers may have antioxidant activities and interfere with drugs that may be affected by the activities of antioxidants.
- Ash bark, leaves, and flowers (Fraxinus ornus) may possess antiviral activity and may increase the effect of antiviral drugs when taken together.
- Ash is not recommended to be used in combination with drugs that alter the immune system.
Interactions with Herbs & Dietary Supplements
- Ash may increase the effect of pain relievers.
- Ash may interfere with how antibacterials work in the body and are not recommended for patients undergoing antibacterial therapy.
- Ash may increase the risk of bleeding when taken with herbs and supplements that are believed to increase the risk of bleeding.
- Ash may increase the effect of anti-inflammatory agents.
- Ash bark, leaves, and flowers may possess antioxidant activities and interfere with drugs that may be affected by the activities of antioxidants.
- Ash bark, leaves, and flowers (Fraxinus ornus) may possess antiviral activity and may increase the effect of anti-viral drugs when taken together.
- Ash bark, leaves, and flowers (Fraxinus ornus) may possess immunomodulatory activities and may increase the effect of herbs on the immune system when taken together.
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 ().
- De Blay F, Bessot JC, Pauli G. [New aero-allergens]. Rev Pneumol.Clin 1996;52(2):79-87.
- Enriquez Palomec O, Hernandez Chavez L, Sarrazola Sanjuan DM, et al. [Aeroallergens, skin tests and allergic diseases in 1091 patients]. Rev Alerg.Mex. 1997;44(3):63-66.
- Ji W, Zhu XX, Tan WF, et al. Effects of Rebixiao granules on blood uric acid in patients with repeatedly attacking acute gouty arthritis. Chin J Integr.Med 2005;11(1):15-21.
- Klein-Galczinsky C. [Pharmacological and clinical effectiveness of a fixed phytogenic combination trembling poplar (Populus tremula), true goldenrod (Solidago virgaurea) and ash (Fraxinus excelsior) in mild to moderate rheumatic complaints]. Wien.Med Wochenschr. 1999;149(8-10):248-253.
- Kostova I. Fraxinus ornus L. Fitoterapia 2001;72(5):471-480.
- Liccardi G, D’Amato M, D’Amato G. Oleaceae pollinosis: a review. Int Arch Allergy Immunol 1996;111(3):210-217.
- Malo J, Cartier A. Occupational asthma caused by exposure to ash wood dust (Fraxinus americana). Eur.Respir.J. 1989;2(4):385-387.
- Mothes N, Horak F, Valenta R. Transition from a botanical to a molecular classification in tree pollen allergy: implications for diagnosis and therapy. Int Arch Allergy Immunol 2004;135(4):357-373.
- Pauli G, Bessot JC, Hutt N, et al. [Pollen environment and its evaluation]. Rev Pneumol.Clin 1997;53(6):317-322.
- Vallverdu A, Garcia-Ortega P, Martinez J, et al. Mercurialis annua: characterization of main allergens and cross-reactivity with other species. Int Arch Allergy Immunol 1997;112(4):356-364.
- von Kruedener S, Schneider W, Elstner EF. A combination of Populus tremula, Solidago virgaurea and Fraxinus excelsior as an anti-inflammatory and antirheumatic drug. A short review. Arzneimittelforschung 1995;45(2):169-171.
- Williams PB. Critical analysis of studies concerning reports of respiratory sensitization to certain wood dusts. Allergy Asthma Proc 2005;26(4):262-267.
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.