Cranberry and pomegranate juices, teas and supplements are widely marketed to boost health and energy. Despite the use of cranberries and pomegranates to prevent urinary tract infections and bolster the immune system, both fruits have the potential to cause side effects.
Eating cranberries or pomegranates or drinking the juice occasionally is safe, according to the National Center for Complementary and Alternative Medicine. However, consuming too much can cause problems.
Types of Side Effects
In excessive amounts, cranberries have the potential to cause diarrhea and stomachaches. When consumed in quantities of more than 1 liter per day for an extended period of time, cranberry juice contributes to the formation of kidney stones in some patients.
People with an allergy to salicylic acid or aspirin are at risk for developing a serious reaction to large amounts of cranberry juice or supplements. When used to treat the skin, pomegranate sometimes causes allergic reactions, such as skin itching or swelling, a runny nose and difficulty breathing.
When combined with blood thinners like warfarin, cranberries increase your risk of developing uncontrollable bleeding, while the combination of pomegranates with drugs that treat hypertension sometimes causes dangerous drops in blood pressure levels. Additionally, using a cranberry and pomegranate product has the potential to increase the side effects of many drugs, including the cancer drug tamoxifen, the epilepsy medication phenytoin, the antidepressant fluoxetine, the narcotic analgesic tramadol and the cholesterol medication rosuvastatin.
Though typically pomegranates and cranberries are safe for pregnant or nursing women individually, consult your doctor before using a product that contains a combination of both, particularly if it is a dietary supplement rather than a type of food or drink.