HORSETAIL Overview Information
Horsetail is a plant. The above ground parts are used to make medicine.
Horsetail is used for “fluid retention” (edema), kidney and bladder stones, urinary tract infections, the inability to control urination (incontinence), and general disturbances of the kidney and bladder.
It is also used for balding; tuberculosis; jaundice; hepatitis; brittle fingernails; joint diseases; gout; osteoarthritis; weak bones (osteoporosis); frostbite; weight loss; heavy menstrual periods; and uncontrolled bleeding (hemorrhage) of the nose, lung, or stomach.
Horsetail is applied directly to the skin to treat wounds and burns.
There have been reports of horsetail products being contaminated with a related plant called Equisetum palustre. This plant contains chemicals that can poison cattle, but toxicity in people has not been proven.
How does it work?
The chemicals in horsetail may have antioxidant and anti-inflammatory effects. Plants related to horsetail contain chemicals that work like "water pills" (diuretics) and increase urine output. But it isn't clear whether horsetail has this effect.
HORSETAIL Uses & Effectiveness 
Insufficient Evidence for:
- Kidney and bladder stones.
- Weight loss.
- Hair loss.
- Gout.
- Frostbite.
- Heavy periods.
- Fluid retention.
- Urinary tract infections.
- Incontinence.
- Use on the skin for wound healing.
- Other conditions.
HORSETAIL Side Effects & Safety
Horsetail is POSSIBLY UNSAFE when taken by mouth long-term. It contains a chemical called thiaminase that breaks down the vitamin thiamine, possibly leading to thiamine deficiency. Some products are labeled "thiaminase-free," but there's not enough information available to know if these products are safe.
Special Precautions & Warnings:
Pregnancy and breast-feeding: Not enough is known about the use of horsetail during pregnancy and breast-feeding. Stay on the safe side and avoid use.Diabetes: Horsetail might lower blood sugar levels in people with diabetes. Watch for signs of low blood sugar (hypoglycemia) and monitor your blood sugar carefully if you have diabetes and use horsetail.
Low potassium levels (hypokalemia): Horsetail might flush potassium out of the body, possibly leading to potassium levels that are too low. Until more is known, use horsetail with caution if you are at risk for potassium deficiency.
Low thiamine levels (thiamine deficiency): There is a concern that horsetail could make thiamine deficiency worse.
HORSETAIL Interactions
Moderate Interaction Be cautious with this combination
- Lithium interacts with HORSETAIL
Horsetail might have an effect like a water pill or "diuretic." Taking horsetail might decrease how well the body gets rid of lithium. This could increase how much lithium is in the body and result in serious side effects. Talk with your healthcare provider before using this product if you are taking lithium. Your lithium dose might need to be changed.
HORSETAIL Dosing
The appropriate dose of horsetail depends on several factors such as the user’s age, health, and several other conditions. At this time there is not enough scientific information to determine an appropriate range of doses for horsetail. Keep in mind that natural products are not always necessarily safe and dosages can be important. Be sure to follow relevant directions on product labels and consult your pharmacist or physician or other healthcare professional before using.
