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Ashwagandha

By

Laura Shane-McWhorter

, PharmD, University of Utah College of Pharmacy

Last full review/revision Jan 2022| Content last modified Sep 2022
CLICK HERE FOR THE PROFESSIONAL VERSION

What is ashwagandha?

Ashwagandha is a small evergreen shrub that grows in India, the Middle East, and parts of Africa.

What claims are made about ashwagandha?

Advocates believe that ashwagandha is an adaptogen Adaptogens "Adaptogen" is a term for certain foods and supplements that are said to help the body cope with "stress." Stress may be psychologic (in the mind), but also may be physical (in the body), and... read more . This herbal medicine term means that this substance is thought to help the body respond to mental and physical stress and to restore normal emotional and physical body function.

In 2020 and 2021, some people began using ashwagandha to diminish the harmful effects of COVID-19, although there is no evidence to support that use.

The long list of other benefits claimed for ashwagandha includes

  • Reducing symptoms of stress that may lead to anxiety and depression

  • Increasing fertility in men

  • Helping people with insomnia sleep

  • Increasing muscle mass, strength, endurance, and energy

  • Reducing inflammation (for example, to help prevent cartilage damage caused by osteoarthritis)

  • Lowering cholesterol and triglyceride levels

  • Lowering blood pressure

  • Improving brain function (including memory)

  • Reducing blood sugar levels in people with diabetes

  • Killing cancer cells

  • Reducing weight gain associated with cortisol (a hormone released in response to stress)

Does ashwagandha work?

Any single compound, including ashwagandha, is highly unlikely to have such a broad range of health benefits.

Studies in laboratories (for example, in cells and organs) have shown that ashwagandha reduces inflammation and relaxes the central nervous system. Studies in mice also suggest that this plant can reduce high blood sugar levels, boost the immune system (although what this means or how this could be done is not clear), and kill cancer cells. The findings from the studies in laboratories and mice have not been confirmed in studies of people.

Small studies in people suggest that ashwagandha might

  • Help reduce stress, anxiety, and fatigue

  • Improve sleep quality in people with insomnia

  • Enhance brain function and help relieve anxiety in people with bipolar disorder

Larger studies in people are needed to confirm the benefits of ashwagandha.

What are the possible side effects of ashwagandha?

Taking ashwagandha by mouth for up to 3 months seems to be safe. Large doses can lead to an upset stomach, diarrhea, vomiting, and, in rare cases, liver problems.

  • Ashwagandha is probably unsafe for pregnant women because it might increase the risk of miscarriage.

  • Whether nursing mothers who take ashwagandha might pass its components into breast milk is unknown. Likewise, the effects of ashwagandha in nursing mothers and infants are unknown.

  • Ashwagandha can irritate the digestive system.

What drug interactions occur with ashwagandha?

  • Ashwagandha might lower blood sugar levels and thus make it unsafe to use with antihyperglycemic (glucose-lowering) drugs (by lowering blood sugar too much).

  • Because of its potential to lower blood pressure, ashwagandha might not be safe in people who take drugs to treat high blood pressure.

  • Ashwagandha, because it seems to make the immune system more active, could also interfere with drugs that suppress the immune system. Examples of these drugs include cyclosporine, mycophenolate, tacrolimus, prednisone, and corticosteroids.

  • Ashwagandha might make people drowsy or sleepy. So combining sedative-hypnotic drugs (used to help with sleep) with ashwagandha might make people too sleepy. Examples of these sedatives are zoldipem, eszoplicone, clonazepam, quetiapine, and lorazepam.

  • Ashwagandha may increase thyroid hormone levels, so doctors carefully monitor thyroid function by ordering blood tests for anyone who takes thyroid hormones and ashwagandha at the same time.

Recommendations

No beneficial health effects of ashwagandha have been confirmed in high-quality studies in people.

Use of ashwagandha is not recommended because there are no confirmed benefits to outweigh the possibility of negative side effects.

Ashwagandha is probably safe for most people; however,

  • Pregnant women, people with stomach ulcers, and those with liver disease should avoid ashwagandha.

  • Women who are breastfeeding and people who take certain drugs (including drugs to suppress the immune system, lower blood sugar, lower blood pressure, and some sedatives) should talk to their doctor before taking ashwagandha.

  • People taking thyroid hormones should also talk to their doctor about taking ashwagandha because blood levels of thyroid hormones may be affected.

Drugs Mentioned In This Article

Generic Name Select Brand Names
NEORAL, SANDIMMUNE
CELLCEPT
PROGRAF
RAYOS
KLONOPIN
SEROQUEL
ATIVAN
NOTE: This is the Consumer Version. DOCTORS: CLICK HERE FOR THE PROFESSIONAL VERSION
CLICK HERE FOR THE PROFESSIONAL VERSION
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