Background

Ashwagandha is an evergreen shrub that grows in Asia and Africa. It is commonly used for stress. There is little evidence for its use as an "adaptogen."

Ashwagandha contains chemicals that might help calm the brain, reduce swelling, lower blood pressure, and alter the immune system.

People commonly use ashwagandha for anxiety, insomnia, and stress. It is also used for asthma, athletic performance, back pain, and many other conditions, but there is no good scientific evidence to support most of these uses. There is also no good evidence to support using ashwagandha for COVID-19.

Don't confuse ashwagandha with Physalis alkekengi. Both are known as winter cherry. Also, don't confuse ashwagandha with American ginseng, Panax ginseng, or eleuthero.

Safety Safety definitions

When taken by mouth: Ashwagandha is possibly safe when used for up to 3 months. The long-term safety of ashwagandha is not known. Large doses of ashwagandha might cause stomach upset, diarrhea, and vomiting. Rarely, liver problems, including severe liver failure and a need for liver transplantation, might occur.

When applied to the skin: Lotion containing ashwagandha is possibly safe when used for up to 2 months.

Special Precautions & Warnings:

Pregnancy: It is likely unsafe to use ashwagandha when pregnant. There is some evidence that ashwagandha might cause miscarriages.

Breast-feeding: There isn't enough reliable information to know if ashwagandha is safe to use when breast-feeding. Stay on the safe side and avoid use.

"Auto-immune diseases" such as multiple sclerosis (MS), lupus (systemic lupus erythematosus, SLE), rheumatoid arthritis (RA), or other conditions: Ashwagandha might cause the immune system to become more active, and this could increase the symptoms of auto-immune diseases. If you have one of these conditions, it's best to avoid using ashwagandha.

Liver disease: Ashwagandha might cause liver damage in some people. But it isn't clear how often this occurs. Until more is known, people with liver disease should avoid taking ashwagandha.

Surgery: Ashwagandha may slow down the central nervous system. Healthcare providers worry that anesthesia and other medications during and after surgery might increase this effect. Stop taking ashwagandha at least 2 weeks before a scheduled surgery.

Thyroid disorders: Ashwagandha might increase thyroid hormone levels. Ashwagandha should be used cautiously or avoided if you have a thyroid condition or take thyroid hormone medications.

Effectiveness

Dosing & administration

Ashwagandha has most often been used by adults in doses up to 1000 mg daily, for up to 12 weeks. Speak with a healthcare provider to find out what dose might be best for a specific condition.

Interactions with pharmaceuticals

Medications changed by the liver (Cytochrome P450 1A2 (CYP1A2) substrates)

Interaction Rating=Minor Be watchful with this combination.

Some medications are changed and broken down by the liver. Ashwagandha might change how quickly the liver breaks down these medications. This could change the effects and side effects of these medications.

Medications changed by the liver (Cytochrome P450 3A4 (CYP3A4) substrates)

Interaction Rating=Minor Be watchful with this combination.

Some medications are changed and broken down by the liver. Ashwagandha might change how quickly the liver breaks down these medications. This could change the effects and side effects of these medications.

Medications for diabetes (Antidiabetes drugs)

Interaction Rating=Moderate Be cautious with this combination.

Ashwagandha might lower blood sugar levels. Taking ashwagandha along with diabetes medications might cause blood sugar to drop too low. Monitor your blood sugar closely.

Medications for high blood pressure (Antihypertensive drugs)

Interaction Rating=Moderate Be cautious with this combination.

Ashwagandha might lower blood pressure. Taking ashwagandha along with medications that lower blood pressure might cause blood pressure to go too low. Monitor your blood pressure closely.

Medications that can harm the liver (Hepatotoxic drugs)

Interaction Rating=Moderate Be cautious with this combination.

Ashwagandha might harm the liver. Some medications can also harm the liver. Taking ashwagandha along with a medication that can harm the liver might increase the risk of liver damage.

Medications that decrease the immune system (Immunosuppressants)

Interaction Rating=Moderate Be cautious with this combination.

Ashwagandha can increase the activity of the immune system. Some medications, such as those used after a transplant, decrease the activity of the immune system. Taking ashwagandha along with these medications might decrease the effects of these medications.

Sedative medications (Benzodiazepines)

Interaction Rating=Moderate Be cautious with this combination.

Ashwagandha might cause sleepiness and slowed breathing. Some medications, called sedatives, can also cause sleepiness and slowed breathing. Taking ashwagandha with sedative medications might cause breathing problems and/or too much sleepiness.

Sedative medications (CNS depressants)

Interaction Rating=Moderate Be cautious with this combination.

Ashwagandha might cause sleepiness and slowed breathing. Some medications, called sedatives, can also cause sleepiness and slowed breathing. Taking ashwagandha with sedative medications might cause breathing problems and/or too much sleepiness.

Thyroid hormone

Interaction Rating=Moderate Be cautious with this combination.

The body naturally produces thyroid hormones. Ashwagandha might increase how much thyroid hormone the body produces. Taking ashwagandha with thyroid hormone pills might cause too much thyroid hormone in the body, and increase the effects and side effects of thyroid hormone.

Interactions with herbs & supplements

Herbs and supplements that might harm the liver: Ashwagandha might harm the liver. Taking it with other supplements that can also harm the liver might increase the risk of liver damage. Examples of supplements with this effect include garcinia, greater celandine, green tea extract, kava, and kratom.
Herbs and supplements that might lower blood pressure: Ashwagandha might lower blood pressure. Taking it with other supplements that have the same effect might cause blood pressure to drop too much. Examples of supplements with this effect include andrographis, casein peptides, L-arginine, niacin, and stinging nettle.
Herbs and supplements with sedative properties: Ashwagandha might cause sleepiness and slowed breathing. Taking it along with other supplements with similar effects might cause too much sleepiness and/or slowed breathing in some people. Examples of supplements with this effect include hops, kava, L-tryptophan, melatonin, and valerian.

Interactions with foods

There are no known interactions with foods.