Are there any dangers or contraindications to taking Ashwagandha?

By analysing around 30 clinical trials evaluating the effect of ashwagandha on health, researchers were able to list the most common side effects[1]. Drowsiness, abdominal discomfort and loose stools were the most frequently reported.

Ashwagandha consmpution, generally in high doses, may cause more severe digestive and intestinal disorders such as nausea, vomiting and diarrhoea.

In rare cases, Ashwagandha may also cause an allergic reaction, particularly in people with an allergy or hypersensitivity to Solanaceae, the family of plants to which ashwagandha belongs to. The Solanaceae family are also known as nightshades, and also includes tomatoes, peppers and aubergines. If you allergic to these foods or other nightshades, there is a possibility you could react to ashwagandha.

Ashwagandha is considered safe at the doses usually recommended, and for people in good health. However, some serious side effects have been reported. Even if they are rare, it is important to be aware of them before taking an ashwagandha food supplement.

In recent years, several cases of liver damage have been reported in the scientific literature after taking ashwagandha in excessively high doses [2],[3]. Patients generally develop jaundice and symptoms, such as nausea, lethargy, itching and abdominal discomfort. Researchers believe that a compound present in ashwagandha extracts is responsible. The compound in question is a withanolide: withanone, which is present in significant quantities in ashwagandha, and to which many of its medicinal properties are attributed. But withanone has chemical groups in its structure - known as toxicophores - which, in medicines, are associated with undesirable effects and toxicity. Fortunately, we have a cellular detoxification system - gluthation - which neutralises these toxicophores, making the drugs containing them safe if used correctly. The same applies to ashwagandha. If taken in recommended doses, despite the presence of withanone toxicophores, our cellular detoxification system makes it safe. However, if taken in high doses, gluthation is no longer able to cope and detoxify the groups responsible for withanone toxicity, which can lead to liver damage[4]. In the majority of cases, liver damage regresses within a few months of stopping ashwagandha and with appropriate treatment.

If you have no particular health problems, ashwagandha poses no health risk, at the recommended dose (500 mg per day). However, there are a number of contraindications, in particular certain drug treatments and certain medical conditions. Ashwagandha is for adults only and should not be given to young children. Do not take ashwagandha food supplements without medical advice, especially if you are in one of the following situations.

There are several drug interactions with ashwagandha, which can, in some cases, increase the effects of medicines and in others oppose them. People taking anti-diabetic or anti-hypertensive medication, immunosuppressants, sedatives or medication for thyroid problems should not take ashwagandha without medical advice.

The same applies if you are taking anxiolytics, such as benzodiazepines. Like benzodiazepines, ashwagandha - which is known to help manage stress - acts on receptors for the neurotransmitter GABA. Therefore, there is a risk that taking ashwagandha at the same time will reinforce the effects of anxiolytics.