CRANBERRY (FOR URINARY TRACT INFECTION)

Cranberry is a type of evergreen shrub that grows in wet areas, such as bogs or wetlands. Cranberry is native to northeastern and northcentral parts of the United States. The shrub has small, dark green leaves, pink flowers, and dark red fruit that are egg-shaped.

Uses

Cranberry is possibly effective for:

Preventing urinary tract infections (UTIs). Some research shows that drinking cranberry juice or taking certain cranberry extracts can lower the risk of repeated UTIs in some people, such as women, children, older people, and people who are hospitalized. But cranberry juice and cranberry extracts don’t seem to prevent repeated UTIs in all people. Also, research comparing cranberry to standard antibiotic treatments used for UTIs is not consistent. Some research shows that cranberry extract works as well as the antibiotic trimethoprim at preventing UTIs. But other evidence shows that cranberry less effective at preventing UTIs compared to antibiotic treatment.

Despite the conflicting results, cranberry products might be an option for PREVENTING recurrent UTI. But it is not clear what the most effective dose is, or if drinking cranberry juice or taking supplements of cranberry extract is more effective.

While cranberry may be effective for PREVENTING UTIs, there is no evidence showing that cranberry is effective for TREATING UTIs.

Warnings

Cranberries contain significant amounts of salicylic acid. Salicylic acid is similar to aspirin. Avoid drinking large quantities of cranberry juice if you are allergic to aspirin.

Drinking more than 1 liter per day for a long period of time might increase the chance of getting kidney stones.

Side Effects

Cranberry is LIKELY SAFE for most people when taken by mouth appropriately. Cranberry juice and cranberry extracts have been used safely in people. However, drinking too much cranberry juice can cause some side effects such as mild stomach upset and diarrhea.

Precautions

Precautions

Pregnancy and breast-feeding: There is not enough reliable information about the safety of taking cranberry for therapeutic reasons if you are pregnant or breast feeding. Stay on the safe side and avoid use.

Children: Cranberry juice is LIKELY SAFE for children when taken by mouth as a food or drink.

Inflammation of the stomach lining (Atrophic gastritis): Cranberry juice might increase how much vitamin B12 the body absorbs for people with atrophic gastritis.

Diabetes: Some cranberry juice products are sweetened with extra sugar. If you have diabetes, stick with cranberry products that are sweetened with artificial sweeteners.

Low stomach acid (hypochlorhydria). Cranberry juice might increase how much vitamin B12 the body absorbs for people with low levels of stomach acid.

Kidney stones: Cranberry juice and cranberry extracts contain a large amount of a chemical called oxalate. In fact, there is some evidence that some cranberry extract tablets can boost the level of oxalate in the urine by as much as 43%. Since kidney stones are made primarily from oxalate combined with calcium, healthcare providers worry that cranberry might increase the risk of kidney stones. To be on the safe side, avoid taking cranberry extract products or drinking a lot of cranberry juice if you have a history of kidney stones.

Interactions

Warfarin (Coumadin) is used to slow blood clotting. Cranberry might increase how long warfarin (Coumadin) is in the body, and increase the chances of bruising and bleeding. Be sure to have your blood checked regularly. The dose of your warfarin (Coumadin) might need to be changed.

Medications changed by the liver (Cytochrome P450 2C9 (CYP2C9) substrates) interacts with CRANBERRY

Some medications are changed and broken down by the liver.

Cranberry might decrease how quickly the liver breaks down some medications. Taking cranberry along with some medications that are broken down by the liver can increase the effects and side effects of some medications. Before taking cranberry, talk to your healthcare provider if you take any medications that are changed by the liver.

Some medications that are changed by the liver include amitriptyline (Elavil), diazepam (Valium), zileuton (Zyflo), celecoxib (Celebrex), diclofenac (Voltaren), fluvastatin (Lescol), glipizide (Glucotrol), ibuprofen (Advil, Motrin), irbesartan (Avapro), losartan (Cozaar), phenytoin (Dilantin), piroxicam (Feldene), tamoxifen (Nolvadex), tolbutamide (Tolinase), torsemide (Demadex), warfarin (Coumadin), and others.

Dosing

ADULTS

For preventing urinary tract infections (UTIs): 10-16 ounces of a cranberry juice cocktail providing 26% cranberry juice daily has been used. 30-300 mL of cranberry juice daily has also been used. 50 mL of a drink containing both cranberry juice and lingonberry juice, taken daily for 6 months, has been used. Capsules containing 400-500 mg of dried cranberry, taken twice daily for 6 months to 1 year, has been used. 500 mg of a specific cranberry extract (Cran-Max, Proprietary Nutritionals) daily, and 800 mg cranberry capsules (Natural Cranberry Extract with Vitamin C, Solgar) twice daily for 6 months has also been used.

CHILDREN

For preventing urinary tract infections (UTIs): 50 mL of a cranberry and lingonberry concentrate taken daily for 6 months has been used. Also, 2 mL/kg of cranberry juice taken daily for one year has been used.