Avoid in individuals with a known allergy or hypersensitivity to juniper. Repeated exposure to juniper pollen may cause occupational allergies that can affect the skin and respiratory tract.
Side Effects and Warnings
The juniper berry has generally recognized as safe (GRAS) status in the United States. The maximum level used in food is 0.006% for the oil and 0.01% for the extract.
Overdose may lead to kidney and skin damage. Overdose symptoms include albuminuria (excessive protein), hematuria (blood in the urine), purplish urine, tachycardia (increased heart rate), hypertension (high blood pressure), convulsions, and metrorrhagia (non-menstrual bleeding from the uterus).
Other possible adverse effects include hypotension (low blood pressure), irritation, blisters, burns, liver toxicity, kidney damage or kidney failure.
Juniper may also lower blood sugar levels. Caution is advised in patients with diabetes or hypoglycemia (low blood sugar), and in those taking drugs, herbs, or supplements that affect blood sugar. Serum glucose levels may need to be monitored by a qualified healthcare professional, including a pharmacist, and medication adjustments may be necessary.
Although not well studied in humans, juniper may also increase the risk of bleeding. Caution is advised in patients with bleeding disorders or taking drugs that may increase the risk of bleeding. Dosing adjustments may be necessary.
Pregnancy and Breastfeeding
Juniper is not recommended in pregnant or breastfeeding women due to the potential for abortions and/or the induction of labor contractions.
Adults (over 18 years old)
There is no proven safe or effective dose for juniper. Tinctures, tablets, capsules and other forms of berry extracts are commercially available. As an infusion, 2-3 grams of dried berries in 150mL of hot water, has been taken by mouth 3-4 times daily. For dyspepsia, 20-50 milligrams of the berry essential oil has been taken twice daily (for up to a maximum of 100 milligrams). This is usually taken as juniper berry tea.
Cade oil (juniper tar) or juniper oil has been typically used pure or partially diluted. It should be noted that application to the skin may be irritating or toxic to the skin. Volatile oil has been applied on the skin three or more times per day.
Children (under 18 years old)
There is no proven safe or effective dose for juniper in children, and use is not recommended
Interactions with Drugs
Juniper may increase the risk of bleeding when taken with drugs that increase the risk of bleeding. Some examples include aspirin, anticoagulants ("blood thinners") such as warfarin (Coumadin®) or heparin, anti-platelet drugs such as clopidogrel (Plavix®), and non-steroidal anti-inflammatory drugs such as ibuprofen (Motrin®, Advil®) or naproxen (Naprosyn®, Aleve®).
Juniper may lower blood sugar levels. Caution is advised when using medications that may also lower blood sugar. Patients taking drugs for diabetes by mouth or insulin should be monitored closely by a qualified healthcare professional, including a pharmacist. Medication adjustments may be necessary.
Interactions with Herbs and Dietary Supplements
Juniper may increase the risk of bleeding when taken with herbs and supplements that are believed to increase the risk of bleeding. Multiple cases of bleeding have been reported with the use of Ginkgo biloba, and fewer cases with garlic and saw palmetto. Numerous other agents may theoretically increase the risk of bleeding, although this has not been proven in most cases.
Juniper may lower blood sugar levels. Caution is advised when using herbs or supplements that may also lower blood sugar. Blood glucose levels may require monitoring, and doses may need adjustment.