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Any time you want to start taking a dietary supplement, it's essential to speak to your doctor first.  You want them to be informed of what you're taking and make sure he thinks it's safe for you.  Talk to your doctor about the safety of adding a cranberry supplement to your weekly routine.  It's best to bring the supplement with you so your doctor can see the dosage, form and other ingredients in the supplement. Talk to your doctor about why you want to take this supplement.  For example, is it for UTI prevention?  Your doctor may also give you other tips to prevent UTIs as well. Make sure to inform you doctor of any other medications or health conditions you have.  Cranberry juice and supplements can interact with certain medications. There have been many, many studies done on cranberry juice supplements on a wide variety of health conditions.  The dosage and type of supplement you take may vary based on the benefit you need.  Cranberry supplements and juice are most commonly used to prevent or treat UTIs.  There is good evidence to support the prevention of UTIs with cranberry supplements.  However, there is little evidence supporting the treatment of UTIs with supplements. One popular use for cranberry supplements is to lower lipid or cholesterol levels.  There is very minimal evidence supporting this. You may also consider using cranberry supplements to prevent stomach ulcer formation from the H. Pylori bacteria. There is moderate evidence to support this. There is very little evidence to support the use of cranberry supplements for the following:  diabetes management, oral health management, prevention of metabolic syndrome and prostate health. Each type of supplement will come with specific dosing instructions.  It's important to read the label thoroughly and figure out how much to take of your cranberry supplement.  On the supplement fact panel (found on the bottle or box) you'll find the serving size information.  If it's a capsule or tablet, it may say something like "1 tablet per serving" or "2 capsules per serving." Make sure you take the amount recommended to help you either prevent a UTI, reduce the likelihood of having an H. Pylori infection or lower your cholesterol levels. Do not take more than the recommended serving daily.  A higher dose won't necessarily provide any additional benefits.  It may also cause more side effects or interfere with other medications you're taking. All supplements have the potential to cause unwanted side effects.  You could experience mild headaches or nausea.  However, they may also interfere with other medications to cause side effects.  Monitor for any changes while you take cranberry supplements.  Most health professionals find cranberry supplements to be safe for most healthy adults.  In addition, many studies have shown little to few side effects associated with supplements.  High doses of either cranberry supplements or cranberry juice have been associated with an increased risk of developing kidney stones due to the oxalate content. Large quantities of cranberry juice, especially 100% cranberry juice, have been occasionally associated with stomach upset and diarrhea. If you notice any of these symptoms, stop your cranberry supplements and talk to your doctor. Although cranberry supplements may help prevent a UTI from forming, it should not be used to treat a current UTI.  Do not take it if you feel you have a current infection.  Cranberry supplements have been thought to acidify the urine which was thought to prevent UTIs from forming; however, recent research shows that its the components of cranberry juice that help prevent the bacteria from sticking to cell surfaces and causing an infection.  There is no research or evidence supporting that cranberry supplements help treat a current UTI.  It should not be taken if you already have been diagnosed with an infection. If you think you have a UTI, talk to your doctor immediately and set up an appointment to do a urine test.  If you test positive for a UTI, the only treatment is antibiotics.

Summary:
Talk to your doctor. Decide what benefit you need from supplementation with cranberry. Follow recommended dosing instructions. Monitor for side effects. Do not take a cranberry supplement if you currently have a UTI or other infection.