Medications & Supplements for Kidney Stone Prevention

Hi, I’m Dr. David Goldfarb.

I’m the director of the Kidney Stone Program at NYU Langone

Health in New York.

I’m a professor of Medicine

and Physiology at the NYU Grossman School

of Medicine, and Dr. Josh Stern of the Kidney Stone Collaborative asked me

to talk about medications

and supplements for prevention of recurrent kidney stones.

My conflict of interest is that my partners

and I invented a supplement, a high citrate beverage,

it’s called Stone Stopper, or Moonstone Stone Stopper,

and it is a high citrate beverage.

Citrate gets into the urine, binds to calcium,

and prevents calcium from binding

to oxalate or to phosphate.

Most kidney stones are made of calcium oxalate, some made

of calcium phosphate citrate is an antagonist

of calcium stone formation.

The other benefit of citrate is that it is metabolized

by the kidney and the liver to bicarbonate.

Therefore, that’s a buffer

and it incu increases the pH of the urine.

And a higher urine pH is important

because that can help prevent uric acid stones

and cystine stones.

So citrate is an important supplement.

You can get it without a prescription.

You can buy a stone stopper online.

The medication that you’ll find that claims

to be a citrate supplement in stores like Vitamin Shop

or GNC, is actually a very low dose.

It’s one milli equivalent

and you want doses of more like 10 to 15 milli equivalents,

two or three times a day, citrate’s well tolerated.

It’s very safe and it is an effective treatment

for kidney stones.

You also don’t have to know if

that your 24 hour urine collection shows a low citrate

to take a citrate supplement.

Other products that are available online

are not so effective.

If you look at the ingredients for many of them,

they contain very tiny doses of medications

that are actually effective.

And so for instance, taking vitamin B six, it’s fine.

But it really only helpful for people

who have a rare genetic disease called primary

hyperoxaluria Type one.

It’s just a few thousand people in the United States with

that abnormality.

So vitamin B six is generally not useful.

You do wanna eliminate vitamin C from your

pill collection

because vitamin C is a score date,

it’s metabolized to oxalate.

And the studies are pretty clear

that people taking vitamin C supplementation will have more

oxalate in the urine and a higher rate

of calcium oxalate stones.

Vitamin D of course, is has a little bit of use

may help a little bit in increasing bone density

and reducing osteoporosis fractures.

It’s very hard to get vitamin D toxic to the point

where you develop high calcium in the blood

or urine and kidney stones.

And most sh most studies have not shown

that people taking vitamin D have an increased rate

of kidney stones unless you take gigantic massive

inappropriate doses.

So taking one or 2000 units a day, I think is probably safe,

although its benefit for increasing bone density

is really slight.

The other choice of medications

that has been a little bit controversial this year are the

thiazides thiazides can help lower urine calcium.

They’re often thought of as diuretics,

but when I prescribe it for people with kidney stones,

I’m not using it to increase urine flow.

That’s your job as somebody increasing your water intake.

I’m prescribing thiazides to reduce urine calcium.

That’s a special effect they have on tubular

kidney, reabsorption of calcium.

So if there’s less calcium in the urine,

fewer kidney stones.

A shorter acting thiazide called hydrochlorothiazide.

HCTZ for short was shown last year

to not be very effective in a study

that was done in the New England Journal in Switzerland.

But there are longer acting drugs

that perhaps are more effective like Indapamide

and Chlorthalidone.

They do have some side effects,

particularly loss of potassium.

So my preference is that when people take those thiazides,

they also take a potassium supplement.

Usually potassium citrate is appropriate.

Sometimes potassium chloride is also acceptable.

Those are prescription medications.

The other side effect that they have,

because they’re often used to lower blood pressure,

blood pressure lowering,

might be a good thing if you have high blood pressure

and if you don’t my preference is for indapamide,

which is a little bit less potent

as a blood pressure lowering agent as compared

to chlorthalidone drugs

that are also used

to increase bone density like bisphosphonates have recently

that like your, your best example of that is

alendronate or Fosamax.

And those drugs have recently been shown

to lower urine calcium

because they’re increasing bone density and

therefore prevent kidney stones.

No one’s ever done a study of those drugs specifically

to prevent kidney stones,

but people taking those drugs for bone density do have

fewer fractures and less kidney stones.

Those are the topics that I wanted

to introduce today and I hope that

that’s been useful for you all.

I appreciate your interest

and support in the Kidney Stone Collaboration.