Ashwagandha Side Effects & Safety:

Ashwagandha, Withania somnifera, is an herb with a long history of use in Ayurvedic medicine. Today, many people supplement with ashwagandha due to its supposed benefits for stress reduction, hormonal …

Photo of author
Written by: Daniel Powers, MS
Published on:

Ashwagandha, Withania somnifera, is an herb with a long history of use in Ayurvedic medicine. Today, many people supplement with ashwagandha due to its supposed benefits for stress reduction, hormonal health, physcial performance, and general vitality. 

Yet, it’s important to understand the overall safety of ashwagandha in order to ensure that it’s appropriate for individuals to take, whether that’s short-term or long-term use.

This article covers everything you need to know about the safety of ashwagandha, including possible ashwagandha side effects, recommended dosage ranges, and whether it’s appropriate based on a variety of individual factors.

ashwagandha side effects and possible interactions

Ashwagandha Overview:

Ashwagandha (Withania somnifera) is an herb found mainly in India, the Middle East, and parts of Africa. It has been used for thousands of years in Ayurveda as well as other traditional medicine systems. 

Traditionally, ashwagandha was used for improving vigor, strength, sexual health, and for rejuvenating the body as a whole. 

Ashwagandha roots in particular were most commonly used due to their more potent effect. The stems and leaves of the ashwagandha plant were occasionally used as well.

Indeed, research has shown that ashwagandha is rich in many bioactive compounds, these include:

  • Withanolides
  • Alkaloids
  • Flavonoids
  • Various vitamins & minerals

These compounds in ashwagandha may exert many different benefits, including:

  • Reduced Stress & Anxiety Symptoms
  • Improved Sleep
  • Enhanced Cognitive Function
  • Improved Hormonal Health & Sexual Function
  • Pain Reduction


Research suggests that Ashwagandha may possess benefits for sleep, cognition, sexual function, overall wellness, and to reduce stress.

Ashwaganda Safety:

Yes, ashwagandha appears safe for most individuals to consume in recommended dosages according to the literature. With that said, there are still possible risks, especially when exceeding the recommended dosage of Withania somnifera

There have been a few reports of liver toxicity associated with ashwagandha consumption, although these are relatively rare. 

Also, it’s important to note that ashwagandha is in the nightshade (solanacea) family, which some individuals are sensitive to. This can lead to inflammation, allergic reactions, and may worsen gut issues such as irritable bowel syndrome. 

Additionally, based on how ashwagandha works in the body, it may not be suitable for individuals with hyperthyroidism, autoimmune disorders (e.g. rheumatoid arthritis, lupus), or men with hormone-sensitive prostate cancer. 

Lastly, it is important to only choose ashwagandha supplements from reputable, trustworthy brands. Ideally, ashwagandha supplements should be third-party tested through accredited labs, with available Certificates of Analysis for important contaminants and other aspects of quality and safety. 

Click here to learn more about the best ashwagandha supplement brands.

Is Ashwagandha safe?

Yes, Ashwagandha is safe for most consumers. Withania somnifera should be used with caution by those sensitive to plants in the nightshade family or have hyperthyroidism, autoimmune disorders, or hormone-sensitive prostate cancer. We recommend speaking with your doctor before taking any new dietary supplements.

Possible Medication Interactions of Ashwagandha:

Ashwagandha may interact with several different classes of medications based on the way it affects various bodily systems. 

First, ashwagandha has potential immunostimulant activities. Therefore, this may impair the effectiveness of immunosuppressant drugs, which are used to slow down an overactive immune system.

Second, given that ashwagandha acts on GABA receptors in the brain, it may intensify the effects of a variety of sedatives or relaxant medications, including: 

  • Benzodiazepines
  • Barbiturates
  • Sleep drugs
  • Muscle relaxants

Finally, some evidence indicates that ashwagandha may interact with hypoglycemic and hypotensive drugs. Thus, individuals taking these medications should use caution.

As always, we recommend talking with your doctor or other trusted healthcare practitioner before taking ashwagandha, especially if you take any of the above medications. 

ashwagandha side effects and health benefits

Ashwagandha Side Effects:

There are a few possible side effects of ashwagandha, including:

  • Drowsiness
  • Sedation
  • Headache
  • Allergic reactions

Additionally, ashwagandha has been reported to cause liver toxicity in some cases. However, these reports are rare and even in these cases, concerns were eliminated after discontinuing use.

Lastly, some users have anecdotally reported anhedonia (lack of pleasure), but this has not been noted in clinical studies of Withania somnifera.

How Much Ashwagandha Should I Take?

According to research, an effective dosage of ashwagandha in a moderate range is 300 to 1,000mg per day. Studies have shown benefits from 120mg all the way up to 12g, but generally, 300mg to 1,000mg daily works best as a starting point for most people. 

Ashwagandha can be taken just once per day, although many studies have also used twice-daily administration with positive effects. Ultimately, it is up to the individual on whether or not to split up the daily dosage. 

Importantly, the potency of the dosage also depends on withanolide concentration. This is why it’s beneficial to choose Withania somnifera supplements with a high concentration of withanolides, preferably 1% or higher. 

Ashwagandha Dosage:

Research indicates that taking between 300mg and 1,000mg of Ashwagandha daily is an effective dosage.

When Should I Take Ashwagandha?

Ashwagandha can be taken essentially any time of day, but there are likely ideal timepoints for each individual based on his or her desired goals and benefits.

For stress and anxiety, one can take ashwagandha in the morning and then in the late afternoon or evening, in order to help reduce stress over the course of the day.

For enhanced testosterone levels, as well as overall vitality and general wellness, supplementing once in the morning and once in the evening works well.

For improved workout performance, it may be best to take ashwagandha before working out and then once more in the day, although pre-workout administration hasn’t been shown to be definitively better than a more general route.

Lastly, to enhance sleep quality, one can take Withania somnifera about 30 to 60 minutes before bed, along with an additional dose earlier on in the day.

General Rationale:

One may wonder how Withania somnifera can be beneficial for seemingly opposing physiological states, such as sleep and exercise performance. 

The reason is because ashwagandha is an adaptogen, which means it can manipulate hormones and other aspects of bodily function depending on what your body needs at that time. 

Specifically, adaptogens work via the Hypothalamic-pituitary-adrenal (HPA) axis, which helps to balance the body’s stress response and achieve homeostasis. If you’re lethargic or depressed, adaptogens can have an energizing effect. However, if you’re overly stressed or anxious, adaptogens may provide a calming and relaxing effect.

Ultimately, this is why ashwagandha may be taken at different points in the day (e.g. morning and night) without causing negative or contradictory effects. 

And given that most clinical trials have used twice-daily administration, this is the recommended route for most people.

With that said, it’s always best to listen to your body and see what works best for you.

Should I Cycle Ashwagandha?

It’s not fully determined if ashwagandha loses its potency over daily, long-term usage, so the importance of cycling ashwagandha is not fully established.

Nonetheless, given the way Withania somnifera affects certain neurotransmitters, hormones, and bodily systems in general, cycling may be effective for resensitizing one to its effects, especially for individuals who are particularly sensitive to it. 

Again, there are no definitive cycling guidelines for ashwagandha. But based on supplement cycles in general, these are potential options for cycling ashwagandha:

  • For shorter-term cycles: Use a “5 days on, 2 days off” approach each week.
  • For longer-term cycles: Supplement for 3 to 6 weeks followed by a 1 to 2-week break, respectively.

How Long Does it Take for Ashwagandha to Work?

According to clinical research, most of the benefits of ashwagandha occurred after 4 to 12 weeks of use. 

Benefits can occur sooner than this, but the greatest effects of Withania somnifera do seem to take time to develop. This is simply because it takes a while for hormones, brain chemicals, and bodily systems to change, especially if one has had long-term issues. 

This doesn’t mean that ashwagandha has no noticeable effects early on. In fact, for some conditions such as pain, ashwagandha may help within hours

Overall, one can expect to notice at least some benefits within the first few days, with the most noticeable benefits after several weeks. 


Daily supplementation with Ashwagandha is thought to begin displaying health benefits within a few days but shows the most benefits after 4 to as weeks of use.

Ashwagandha vs. Other Herbs:

Ashwagandha, also called Withania somnifera, is often compared to many other different types of herbs. We have compiled a few helpful articles going over common comparisons.

Ashwagandha vs. Cistanche

Ashwagandha vs. Eleuthero

Ashwagandha vs. Ginseng

Ashwagandha vs. Holy Basil

Aswagandha vs. L-Theanine

Aswagandha vs. Maca

Ashwagandha vs. Melatonin

Ashwagandha vs. Rhodiola

Ashwagandha vs. Shilajit

Ashwagandha vs. Tongkat Ali

Ashwagandha vs. St. John’s Wort

Ashwagandha vs. Valerian Root

Read More:

Below, we’ve put together several additional articles going over more information regarding the herb Ashwagandha.

Ashwagandha Benefits: Dosage & Safety

• Ashwagandha Dosing: How Much Should You Take Per Day?

Benefits of Ashwagandha for Anxiety & Stress

• Benefits of Ashwagandha for Men

Benefits of Ashwagandha for Sleep

• Benefits of Ashwagandha for Women

Best Ashwagandha Supplements

ashwagandha side effects and safety


Ashwagandha is a powerful herb with potential health benefits for stress and anxiety, sleep quality, hormonal health, brain function, and more.

Research indicates that ashwagandha is generally safe to take for most individuals when used in the appropriate doses from high-quality products. 

However, there still are possible side effects, and it may not be safe for various individuals. Withania somnifera may also interact with various medications, including sedatives, benzodiazepines, and hypoglycemics, among others.

We always recommend consulting your doctor before taking any supplement, which includes ashwagandha. When paired with these guidelines, one has a greater chance of experiencing the benefits of ashwagandha while minimizing any risks or side effects.

Photo of author

About Daniel Powers, MS

Daniel has a master's degree in herbal science from the Maryland University of Integrative Health. He has a passion for herbal medicine and how it can be used to support everyday health & wellness.