Ashwagandha (Withania somnifera)
Natural Standard Bottom Line Monograph, Copyright © 2013 (www.naturalstandard.com). Commercial distribution prohibited. This monograph is intended for informational purposes only, and should not be interpreted as specific medical advice. You should consult with a qualified healthcare provider before making decisions about therapies and/or health conditions.
While some complementary and alternative techniques have been studied scientifically, high-quality data regarding safety, effectiveness, and mechanism of action are limited or controversial for most therapies. Whenever possible, it is recommended that practitioners be licensed by a recognized professional organization that adheres to clearly published standards. In addition, before starting a new technique or engaging a practitioner, it is recommended that patients speak with their primary healthcare provider(s). Potential benefits, risks (including financial costs), and alternatives should be carefully considered. The below monograph is designed to provide historical background and an overview of clinically-oriented research, and neither advocates for or against the use of a particular therapy.
Ajagandha, amangura, amukkirag, asan, asgand, asgandh, asgandha, ashagandha, ashvagandha, ashwagada, ashwaganda, ashwagandholine, asoda, asundha, asvagandha, aswagandha, avarada, ayurvedic ainseng, clustered wintercherry, ghoda asoda, Indian ginseng, kanaje Hindi, kuthmithi, samm al ferakh, Solanaceae (family), winter cherry, withania, Withania coagulans, Withania somnifera, Withania somniferum, Withania somnifera Dunal, Withania somnifera glycowithanolides, Withania somnifera Kaul, withanolide A (WL-A).
Ashwagandha (Withania somnifera) is a small evergreen shrub that grows to about four or five feet tall. It is found in dry areas of India and the Middle East, as well as parts of Africa. Ashwagandha has been used in Ayurvedic medicine in India for hundreds of years as an "adaptogenic" herb (rasayana), meaning that it is used with the intention to help the body resist physiological and psychological stress. It is purported to tone, normalize, and revitalize bodily functions.
The potentially active parts of ashwagandha include alkaloids and steroidal lactones that together are called withanolides (particularly withaferin A), and preparations are often standardized to their percentage content of withanolides. Although used for a wide variety of medical conditions, there is currently insufficient scientific evidence to conclude the efficacy of ashwagandha for the prevention or treatment of any specific condition.
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.
Diabetes (type 2)
Based on early study, ashwagandha may decrease blood sugar levels. Additional evidence is required in this area before ashwagandha can be recommended for diabetes.
Increases in urine volume have been reported with ashwagandha use. Additional evidence is required in this area before ashwagandha can be recommended as a diuretic.
Decreases in serum total cholesterol levels, triglycerides, low-density lipoprotein (LDL), and very low-density lipoproteins (VLDL) have been reported with ashwagandha use. Further research is needed before a strong recommendation can be made.
The use of ashwagandha as an anti-aging agent is based on traditional use in Indian Ayurvedic medicine to promote physical and mental health, improve resistance to disease, and promote longevity. Human research is lacking in this area, and currently there is insufficient evidence to draw a firm conclusion.
The use of ashwagandha in osteoarthritis has been suggested based on its reported anti-inflammatory and anti-arthritic properties. Well-designed human research is needed to confirm these results.
There is insufficient scientific evidence to recommend the use of ashwagandha in the management of Parkinson's disease.
*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 against this use (it may not work); F: Strong scientific evidence against this use (it likely does not work).
The below uses are based on tradition or scientific theories. 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 health care professional.
Activity stimulant, adaptogen, allergic reactions, Alzheimer's disease, anaphylaxis, antibacterial, antifungal, antioxidant, anti-tumor, anxiety, aphrodisiac, asthma, astringent, atherosclerosis/hyperlipidemia (lipid peroxidation), back pain, boils, bronchitis, cancer, carbuncles, cardiovascular disease, chemotherapy, cognitive improvement, depression, emaciation, emmenagogue (menstrual blood flow stimulant), endocrine conditions, exercise performance, fatigue, fibrosarcoma, hay fever, hemiplegia, hematopoesis, hiccups, HIV, immunostimulant, infertility, insomnia, kidney protection, liver conditions, lung conditions, lymphoma, memory improvement, menstrual disorders, mood stabilization, nervous exhaustion, neurodegenerative diseases, neurological disorders, parasitic infections (ring worm), radiosensitization, rejuvenation, senile dementia, skin pigmentation disorders (leukoderma), skin ulcerations, stress, stroke, tardive dyskinesia, testicular development, tonic, toxicity (genotoxicity), tuberculosis, ulcers.
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.
Adults (over 18 years old)
There is no proven effective dose for ashwagandha in adults. Various preparations are commercially available, including capsules, powders, teas, tinctures, decoctions and multi-herb formulas.
In capsule form, 1-6 grams daily of the whole herb has been used. As a powder, 3 grams of powder taken two times daily in boiled warm milk, have been used. A tea has been made by simmering/boiling 1 part root in 10 parts water for 15-30 minutes and taken twice daily in the amount of 1/2 to 1 ounce at a time. 1-6 grams daily of the whole herb in tea form has been used. Tinctures or fluid extracts have been dosed at 2-4 milliliters, taken 3 times daily. Tinctures may contain high concentrations of alcohol. As a milk decoction, 5 teaspoons of dried herb in 1 cup boiling liquid, taken as 2-3 cups per day with raw sugar or honey, has been used. As multi-herb formulas, 3-12 grams have been used in combination with other herbs.
Injected use is not recommended as human data are lacking.
Children (under 18 years old)
Overall, there is insufficient evidence available to recommend use of ashwagandha in children. Children 8-12 years-old have been given 2 grams daily in milk for 60 days with no toxicity reported in one trial. In Ayurveda, ashwagandha is considered acceptable to give to debilitated children, however data from clinical trials is lacking.
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 if sensitive or allergic to ashwagandha products or any of their ingredients. Dermatitis (allergic skin rash) was reported in three of 42 patients in one ashwagandha trial.
Side Effects and Warnings
There are few reports of adverse effects associated with ashwagandha, although there are scant human trials using ashwagandha, and most do not report the doses or standardization/preparation used.
Ashwagandha may cause sedation, possible life-threatening respiratory depression, decrease blood pressure and cause abnormal heart rhythms. Ashwagandha may cause diarrhea. Nausea and abdominal pain have also been reported. Theoretically, irritation of mucous and serous membranes may occur, and ashwagandha should be avoided in peptic ulcer disease.
Ashwagandha may lower blood sugar levels, based on limited human research (in patients with type 2 diabetes), and therefore may interact with diabetic medications, although the mechanism is unknown.
Ashwagandha has been reported to possess diuretic properties, and kidney lesions may occur. Ashwagandha may stimulate thyroid function and increase T4 levels, possibly increasing risk of hyperthyroidism. Ashwagandha may also possess androgenic (testosterone-like) properties, based on rat evidence of increased testicular weight and spermatogenesis, as well as decreased serum FSH and testosterone levels.
Ashwagandha may stimulate red and white blood cell production, and increase platelet count, although there is limited study in these areas and mechanism is unknown. Ashwagandha is rich in iron.
Ashwagandha may possess immunomodulatory and anti-inflammatory effects.
Pregnancy & Breastfeeding
Ashwagandha is not recommended due to a lack of available scientific evidence. Ashwagandha may cause abortions.
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.
Interactions with Drugs
In theory, ashwagandha may increase the effects of amphetamines.
Ashwagandha may possess androgenic (testosterone-like) properties, based on rat evidence of increased testicular weight and spermatogenesis.
Ashwagandha has been reported to significantly increase coagulation time, although the significance in humans is not clear. In theory, effects may be additive with anticoagulants.
Based on limited human research (in patients with type 2 diabetes), ashwagandha may lower blood sugar levels and therefore may interact with diabetic medications, although the mechanism is unknown.
Ashwagandha may lower systolic and diastolic blood pressure, and may therefore alter the effects of blood pressure lowering drugs.
Ashwagandha has been associated with cholinesterase inhibition, and caution is warranted when taken with cholinesterase inhibiting medications. Examples of cholinesterase inhibitors include: donepezil (Aricept®), rivastigmine (Exelon®), galantamine (Reminyl®), tacrine (Cognex®), neostigmine (Prostigmin®), edrophonium chloride (Tensilon®), and pyridostigmine bromide (approved by the U.S. Food and Drug Administration (FDA) for use after exposure to the nerve gas Soman).
Ashwagandha extract may reduce cyclophosphamide-induced immunosuppression/leukopenia and urotoxicity. Caution is advised when taking ashwagandha with cyclophosphamide or immunomodulating drugs.
Although not well studied in humans, ashwaganda may increase paclitaxel's effectiveness on lung cancer. Repeated administration of ashwagandha may attenuate the development of tolerance to narcotics. Ashwagandha may also improve tardive dyskinesia symptoms caused by haloperidol (Haldol®).
Ashwagandha may cause sedation and possible life-threatening respiratory depression, and may interact with sedatives, hypnotics, or other central nervous system depressants. In early research, ashwagandha was reported to increase the effects of barbiturates and ethanol.
Ashwagandha may cause hyperthyroidism based on data suggesting thyroid stimulation and increased T4 serum levels, and therefore may interact with drugs for hyperthyroidism or hypothyroidism.
Ashwagandha may also interact with diuretics (water pills) or chemotherapy agents.
Interactions with Herbs & Supplements
Ashwagandha may reduce 5-HTP (5-hydroxytryptophan) levels.
Although not well studied in humans, ashwagandha has been reported to stimulate thyroid function, including increased serum T4 concentrations.
Ashwagandha has been reported to significantly increase coagulation (blood clotting) time, although the significance in humans is not clear. In theory, effects of anticoagulant agents and the risk of bleeding may be increased.
Based on limited human research (in patients with type 2 diabetes), ashwagandha may lower blood sugar levels and therefore may interact with diabetic agents, although the mechanism is unknown.
Ashwagandha may lower systolic and diastolic blood pressure, and may therefore increase the effects of other hypotensive (blood pressure lowering) agents.
Ashwagandha is rich in iron. Ashwagandha also contains arginine, and may therefore add to the total dose and effects when taken with arginine supplements.
Ashwagandha contains ornithine, and may therefore add to the total dose and effects when taken with ornithine.
Ashwagandha may possess androgenic (testosterone-like) properties, based on rat evidence of increased testicular weight and spermatogenesis. Saw palmetto possesses 5-alpha reductase properties similar to finasteride (Proscar®), and may antagonize potential androgenic effects of ashwagandha.
Ashwagandha may cause sedation and possible life-threatening respiratory depression, and may interact with sedatives, hypnotics, or other central nervous system depressants.
Ashwagandha may also interact with diuretics (water pills).
This information is based on a systematic review of scientific literature edited and peer-reviewed by contributors to the Natural Standard Research Collaboration (www.naturalstandard.com).
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 www.naturalstandard.com. Selected references are listed below.
Andallu B, Radhika B. Hypoglycemic, diuretic and hypocholesterolemic effect of winter cherry (Withania somnifera, Dunal) root. Indian J Exp Biol 2000;38(6):607-609. View Abstract
Bucci LR. Selected herbals and human exercise performance. Am J Clin Nutr 2000;72(2 Suppl):624S-636S. View Abstract
Kulkarni RR, Patki PS, Jog VP, et al. Treatment of osteoarthritis with a herbomineral formulation: a double- blind, placebo-controlled, cross-over study. J Ethnopharmacol 1991;33(1-2):91-95. View Abstract
Kuppurajan K, Rajagopalan SS, Sitoraman R, et al. Effect of Ashwagandha (Withania somnifera Dunal) on the process of ageing on human volunteers. Journal of Research in Ayurveda and Siddha 1980;1(2):247-258.
Nagashayana N, Sankarankutty P, Nampoothiri MR, et al. Association of L-DOPA with recovery following Ayurveda medication in Parkinson's disease. J Neurol Sci 2000;176(2):124-127. View Abstract
Spelman K, Burns J, Nichols D, et al. Modulation of cytokine expression by traditional medicines: a review of herbal immunomodulators. Altern Med Rev. 2006 Jun;11(2):128-50. View Abstract
Upadhaya L, et al. Role of an indigenous drug Geriforte on blood levels of biogenic amines and its significance in the treatment of anxiety neurosis. Acta Nerv Super 1990;32(1):1-5.
Venkataraghavan S, Seshadri C, Sundaresan TP, et al. The comparative effect of milk fortified with Aswagandha, Aswagandha and Punarnava in children - a double-blind study. J Res Ayur Sid 1980;1:370-385.
Copyright © 2013 Natural Standard (www.naturalstandard.com)
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.
March 22, 2017