Horsetail is a plant which produces leaves, stems, flowers and roots that can be used in holistic medicine. There is only very limited evidence supporting the use of horsetail to treat any disease or condition, but it is most commonly used as a remedy for hair loss, gout, fluid retention and kidney disease. In general, horsetail is safe and associated with few side effects. However, there are a few horsetail contraindications, or circumstances under which the product should not be used.
Avoid horsetail supplements if you fall into any of the following groups of people. You may be at high risk of experiencing serious side effects if you are in any of these susceptible categories.
No studies have evalauted horsetail’s safety and efficacy for pregnant women. It may trigger contractions in the uterus, increasing the risk of miscarriage or preterm labor. Additionally, horsetail could theoretically incraese the likelihood of birth defects or other health problems in the baby. Until more is known, pregnancy is regarded as a horsetail contraindication.
People with Low Potassium
If you have low potassium levels, or hypokalemia, you should avoid horsetail supplements. Horsetail may increase the rate at which potassium is eliminated from the body. This could lead to potassium levels that are dangerously low, particularly for people with pre-existing hypokalemia. If you are at risk for potassium deficiency, use horsetail with extreme caution and only under the guidance of a qualified health care provider.
People with Thiamine Deficiency
Horsetail may flush thiamine, a water-soluble B-vitamin, from the body at a faster rate. If you have low thiamine levels or thiamine deficiency, do not use horsetail. It could worsen the condition, leading to potentially serious complications.
There are some other dangers and side effects associated with horsetail. Visit the National Institutes of Health website for more information about horsetail contraindications, side effects and risks.