Ashwagandha (Withania somnifera) vs Kava (Piper methysticum)

Ashwagandha (Withania somnifera)

Kava (Piper methysticum)

About

Ashwagandha (Withania somnifera), sometimes called “Indian ginseng,” is a sturdy shrub growing to about 5 ft (1.5 m) with oval leaves, greenish or yellow flowers, and small, round fruits. NCCIH says some preparations may help insomnia and stress, but there isn't enough evidence to know whether it helps most other conditions.

Kava (Piper methysticum), a member of the pepper family native to the South Pacific, has been made into ceremonial and medicinal drinks by Pacific Islanders for thousands of years. Kava products are promoted for anxiety and other health conditions; NCCIH says kava supplements may help anxiety, but there isn't enough evidence to show whether kava helps any other condition.

Safety & precautions

Liver: Liver injury linked to ashwagandha supplements is rare but has been reported (NCCIH), and LiverTox places it in its likely-cause category (B). Stop and seek advice if you notice yellowing skin or eyes, dark urine or itching. Pregnancy & Breastfeeding: NCCIH says to avoid it during pregnancy and not to use it while breastfeeding. Thyroid: ODS notes it might affect thyroid function. Nightshade Sensitivity: This herb can cause adverse reactions in those sensitive to the nightshade family. Digestive Sensitivities: Some individuals may find it hard to digest ashwagandha.

Liver injury: Rare but severe liver injury, including hepatitis, cirrhosis, liver failure needing a transplant, and death, has been reported with kava products. LiverTox puts kava in its top likelihood category (A) for causing liver injury, with symptoms usually starting within weeks to a few months of use. MSK describes a case of liver failure and transplant after about two months of use with no sign of overdosing. In March 2002 the U.S. FDA issued a consumer advisory on this risk, and several countries restricted kava or removed it from sale. Do not use kava if you have liver disease or drink alcohol, and talk to a doctor first if you take medicines that can affect the liver. Stop and get medical advice if you notice yellowing skin or eyes, dark urine, or unusual tiredness. Sedation: Kava can impair driving and adds to the effects of alcohol and sedatives. Pregnancy & Nursing: Not recommended. Legality: Subject to restrictions in many countries.

Safety text above is printed in full and is never abbreviated. For each plant’s complete precautions, drug and food interactions and preparation notes, open its own page - both are free.