The Toxicity of Juniper Berries

Juniper berries are used in herbal medicine, and also flavor certain foods and gin. Although they are called berries, they are part of the cone and not a true berry. Most people can safely consume juniper berries in the amounts used in food, but some people should avoid consuming juniper in medicinal amounts.

Although further research is needed to determine whether juniper is effective in treating any health condition, herbalists sometimes use it to stimulate menstruation, as a diuretic and to treat bladder infections. Traditionally, juniper berries were also used for treating urinary tract infections, heart failure and gonorrhea, according to Beth Israel Deaconess Medical Center.

Speak with your doctor before consuming juniper berries to make sure it is safe for you. The traditional dosage for juniper berry was between 2 and 10 grams of berries or 20 to 100 milligrams of essential oil. You can also make juniper tea with either the berries or the twigs of the juniper tree, straining the tea before drinking it. Drink only 1 to 2 cups per day, as consuming too much juniper berry can cause unpleasant effects.

Some people are allergic to juniper berries, and experience allergic reactions including itching, rash, swelling and difficulty breathing. If you are pregnant, do not consume juniper berries as this could cause you to miscarry. Also, juniper berry can interact with lithium, so people using this medication should avoid consuming these berries.

When you consume large amounts of juniper berries, it could cause mild toxicity symptoms due to the volatile oils it contains, including thujone, notes North Carolina State University. These symptoms are usually limited to diarrhea. However, Drugs.com notes that large doses may also cause kidney damage, convulsions and DNA damage.