What are cranberry pills?

Cranberry pills are supplements made from dried, powdered cranberries.

They sometimes contain other ingredients, like vitamin C, probiotics, or D-mannose to help combat urinary tract infections.

What are cranberry pills used for?

They are most often taken to prevent recurring urinary tract infections (UTIs).

Cranberry pills contain proanthocyanidins that prevent E.coli from sticking to the wall of the urinary tract & causing an infection. (E. coli is the most common type of bacteria to cause UTIs) (123).

They are also rich in antioxidants. Taking 1200 mg of cranberry extract daily for 8 weeks reduces oxidative stress in the body (400 mg/day was not enough to have any effect) (45).

Do they actually help prevent urinary tract infections?

Some studies have found that taking cranberry pills daily for 2 months can help reduce the number of UTIs in women who get them frequently (67, 89).

But other studies have found no benefit in elderly people in nursing homes or people with neurogenic bladder disorders (10111213).

Studies comparing cranberry pills to antibiotics for the prevention of UTIs have had conflicting results (1415).

What dosage is most effective?

Studies have found 500 to 1,500 mg/day to be effective at preventing UTIs (5141617).

Products containing at least 25% proanthocyanidins or 36mg/serving seem to be the most effective (11181920).

1,200 mg/day is effective at reducing oxidative stress (5).

What are some recommended brands??

Cranberry pills are available over the counter at drug stores or online.

One of the most common brands is Azo.

Most professional grade supplement lines also have cranberry products. For example, Pure Encapsulations has the following cranberry products:

  • Cranberry NS – 500 mg capsules of cranberry extract, dosage 1-3/day between meals
  • Cranberry/D-Mannose – 100 mg cranberry extract + 450 mg D-mannose + 11 mg ascorbyl palmitate (fat-soluble vitamin C), dosage 2-6/day between meals
  • PureBiOme – 4 probiotic strains (17.5 CFUs) + 300 mg cranberry extract per capsule, dosage 2/day w. meals

Are there any side effects?

There have been reports of minor side effects, like stomach discomfort, abdominal pain, or increased urinary frequency in some people (5121421).

What are the contraindications?

Cranberries are high in salicylates, so people who have a salicylate sensitivity may want to avoid cranberry pills (22).

There might be a risk of developing calcium-oxalate kidney stones, but research on the topic is mixed (23, 2425).

People on blood thinners like Warfarin may also want to avoid cranberry pills. A couple of studies have found an interaction, but there is no clear consensus (2627).