Valerian root (Valeriana officinalis) is a natural sedative and anxiety reliever that can be helpful for people with insomnia, anxiety, and other sleep disorders. However, there are some people who should not take valerian root. Pregnant women should avoid taking valerian, as it can stimulate the uterus and may cause a miscarriage.
In addition, people with liver disease or epilepsy should also avoid taking valerian. People with high blood pressure should be careful to avoid taking too much valerian root; it can cause blood pressure to go too low. Individuals with hyperthyroidism or hypothyroidism may also have an increased risk of side effects from valerian.