ZismanUCThe featured image points to a widespread idea now on the web concerning how cola drinks might promote kidney stone passage. It has been called the ‘Coke Treatment for Kidney Stones.‘ Fluids are valuable for all stone formers, but the suggested usage may not be ideal and this post points out some of the drawbacks.


A few months ago, a delightful 71-year-old woman presented to our clinic for a metabolic evaluation to try to stop her chronic kidney stones. She passed her first kidney stone about 5 years ago. A year later she developed another kidney stone, which required shockwave lithotripsy therapy. Ultimately her stone was analyzed and she was told it was a “calcium stone.” Over the following few years, she continued to pass one stone per year. More recently, the frequency had increased to a few times per year. Frustrated with the frequent stone recurrences, she sought information online regarding potential remedies for recurrent stone disease. On several websites she came across a remedy known as the “Coke treatment,” which was purported to dissolve kidney stones and prevent stone recurrence. She sent in her payment of $39.97 and received a booklet instructing her to do the following:

  • drink 72 ounces of Coca Cola, ideally not diet or caffeine-free, in 15 minutes or as fast as possible
  • steam and puree one-half pound of asparagus and drink immediately
  • repeat as necessary until kidney stone pain is resolved and stones have passed
  • some variations of this treatment that can be found on the web also recommend drinking water for several hours after the treatment

She dutifully followed the instructions provided and found that on the day of her acute pain, her symptoms did, indeed, abate. Unfortunately, over the next year she found the frequency of her stone attacks actually increased – most recently to as often as passing gravel 2 to 3 times weekly (with significant discomfort). To combat this she has been using the “Coke treatment” about 2-3 times weekly over the last year, creating an apparent vicious cycle (more on that later). Finally, her daughter insisted that she see a physician and so she presented to our office, wondering why her treatment hasn’t been effective.


Using the term ‘Coke treatment of kidney stones’ yielded about 108,000 results, and by page 10 the treatment was still prominent. So cola drinks as a treatment is current.

claim in Internet lore is that phosphoric acid, an additive used in dark colas, when consumed in large quantities can facilitate a reaction within the kidney that will dissolve the calcium oxalate or calcium phosphate admixture that is the kidney stone.  One finds variants of this claim in the discussions by patients.

As I pictured this poor older woman chugging a 6-pack of Coke 2-3 times per week with an asparagus chaser, I was curious to determine whether any potential scientific merit to the internet solution exists.

In short, the answer is No.

Allow me take you through some of the details.


Fluids are Useful

I will start with the 72-ounces of Coca Cola that are to be ingested rapidly. Of course, if one is having acute renal colic with a small stone stuck in a tiny structure like the ureter or urethra, drinking over two liter of fluids of any sort is likely to be beneficial in attempting to propel the stone forward and out of the body. But why Coca Cola? Or any cola for that matter? Is there some reason to believe cola drinks have special properties as a stone treatment?

As far as I can tell, no.

Cola Drinks Are Not a Proven Remedy

Phosphoric Acid as a Stone Dissolver

Phosphoric acid, mixed with nitric acid, is used as a cleaner in the beer industry to remove beerstone (calcium oxalate) from beer kegs. It is also used in home cleaning solutions, as an industrial etchant, and as a rust remover. This leads to the false impression that drinking acid phosphates in beverages will create conditions in the kidneys like those in the beer kegs.

In beer kegs, and when you clean your floor with cleaners, high concentrations of a strong acid are applied directly to the unwanted material.

You Can’t Get Phosphoric Acid into the Urine

But when the small quantities of phosphoric acid found in dark colas are ingested, the first thing that will happen is that calcium and magnesium binding will occur in the gastrointestinal tract. By the time the remaining phosphoric acid is absorbed, additional buffering will occur in the blood and bone, so essentially neutral – not acid – phosphate will be delivered to site of the stone. In studies of a neutral phosphate’s effect on crystal inhibition and dissolution, no evidence of crystal dissolution has been noted.

Effects of Cola in People

How about real people, instead of crystals?

Cola Drinks Raise Stone Risk in Urine

Four subjects were asked to drink three quarts (96 oz) of a dark cola over the course of 48 hours. The researchers then compared the amounts of 3 urine constituents that are known to affect the likelihood of stone formation: magnesium (higher levels in the urine are associated with DECREASED likelihood of stone formation), citrate (higher levels are associated with DECREASED likelihood of stone formation) and oxalate (higher levels are associated with INCREASED likelihood of stone formation). In this study, the average 24-hr magnesium excretion decreased by 2.6 mg, the average citrate excretion decreased by 122 mg, and the average oxalate excretion increased by 8.6 mg.  So in fact, in each of the three constituents, the effect of the cola was a worsening of stone risk.

A larger study performed a few years later confirmed these findings, as well as an associated increase in supersaturation for calcium oxalate in a group of 45 subjects.

Cola Drinks Raise Statistical Risk of Stones

In nearly 200,000 individuals who have been followed over time, Ferraro and colleagues analysed the association between consumption of sugar-sweetened colas and kidney stone formation. Subjects consuming the most sugar sweetened colas were 23% more likely to develop a kidney stone than those in the lowest consumption group. In general cola type drinks are exactly the wrong ones for stone prevention.

Cola Drinks May Pose Other Health Hazards

Sugar and Sodium

The suggested amount of regular Coke in the ‘Coke treatment’ has 840 calories, 270 mg of sodium, and 39 grams of sugar. Taking in that many calories from sugar will almost certainly reduce the amount of other nutrients that one is able to eat or drink in a day, while sugar and sodium are both directly linked to higher urine calcium excretion, a key contributor to nephrolithiasis.

Bone Disease

Whether because of substitution for milk-based drinks, or due to the high acidity associated with soft drinks, consumption of increasing quantities of carbonated beverages has been linked to osteoporosis.

Kidney Disease

In addition to the well known association with diabetes and obesity, a recent report has linked higher consumption of dark colas (2 cans or more per day) with risk of chronic kidney disease.


Ancient Beliefs

Asparagus has been cultivated in the Mediterranean region and in Asia for over 2000 years. Egyptians, Greeks, and Romans believed asparagus to have medicinal properties ranging from treating mood disorders to rheumatism, and a 15th century Arabic sex manual entitled “The Perfumed Garden” claimed asparagus has aphrodisiac properties. It is believed by many to have diuretic properties.

Not Our Asparagus

The usual variety of asparagus that we would buy at the store, Asparagus officinales, is a different species than the medicinal Asparagus racemosa, which is commonly grown in Asia. Furthermore, the medicinal use of asparagus typically involves the root, not the shoot that we typically eat. In Germany, for example, asparagus root is approved by an herbal oversight board as a diuretic whereas the shoot is not recommended.

Not Any Asparagus?

How good is the evidence? Despite what the herbal board says, a recent review found no evidence for human use of the asparagus root as a diuretic. And what if it were a potent diuretic, for argument’s sake? It would have to have specific effects in the distal convoluted segment (a particular region of the kidney tubule), like the thiazide diuretics, to have any beneficial effects on stone prevention –and certainly unlikely to be effective in the acute setting.

So What’s the Harm in a Lot of Asparagus? 

Generally, not much. In normal quantities it is  a healthy vegetable loaded with nutrients such as folate, potassium, and vitamin C. For a stone former, however, there may be hidden dangers with a high asparagus intake. Asparagus has a moderate amount of oxalate, and this amount adds up quickly with repeated administrations of such treatments as the ‘Coke treatment.’ Furthermore, vitamin C is also metabolized to oxalate in the body, adding more of the lithogenic substance to the urine. So, as with most things (except water), it seems that moderation is key.


Looking back,our patient appears to have increased her stone attack frequency with the help of the “Coke treatment” from yearly to several times per week. It seems that the remedy was indeed worse than the disease.

During our visit, in preparation for which she performed several 24-hour urine collections, we determined an individualized plan for her kidney stone treatment based on her urine parameters and a thorough history. With a steady increase in her daily fluid intake and the addition of thiazide therapy, at last check she has had no further stone episodes.


On a hot Summer day, a can of Coke can be delightful. As a medical treatment for kidney stones, no cola is as good as plain water. In the very high doses of the ‘Coke treatment’ there is no benefit predicted from what science we have, and no data to show benefit from a clinical trial. In fact, it would be difficult to organize and perform a clinical trial of the ‘Coke treatment’ because of its evident potential for harm. The trial would be unlikely to pass the human subject protection board review.

Don’t do it.

You Might Want to Read:

Kidney Stone Pain

Fluids to Prevent Stones

Citrate to Prevent Stones

What Stones Are

Types of Kidney Stones






  1. Ro Yale

    I used the Coke remedy for a stone that was too big to pass thru my kidney and it worked. I had to do the treatment twice and it worked. I have been stone free for at least 10 years now.

  2. Liz

    I wonder how this myth got started. I say that because this is something the Amish are known to use as a “remedy” back home, (Northeast Missouri). I dont know that all the Amish did, just a few, or if it was a regional thing but we aren’t talking about people who use the internet. Maybe a few just picked it up word of mouth from locals who saw it on the internet. Hard to say. Can’t go back that far. Perhaps its something associated with Coke’s beginning and having been created by a doctor. However it was not created as a medicine.

  3. Matthew

    I was at the E R yesterday trying to figure out what the pain was about. After a lots of testing it was determined that I have a kidney stone.

    I decided to order on the way home a MC Donalds comobo extra large with coke. I decided to drink it all really fast.
    Since the ER wouldn’t allow me to eat or drink due to a long day of back to back testing.

    The results…? it didn’t cure my kidney stone, but it did help move it a long to a different place.
    My pain triggers are now different after drinking the coke. I still have the pain but the stone seems to be moving along or relocated its position

    I’ll try the remedy above to see if it works.

    • jharris

      Hi Matthew,
      I think water would have done the same thing. It is fluids that helped, not necessarily coke.
      Best, Jill

  4. Rodney Hamp

    I tried it ands it worked amazingly. I was instructed by a holistic Dr to drink 1 warm 12 once can of Coke every hour for eight hours. For you that beleive everything the medical community says, ask youself a question. If coke can desolved rust, what do you think it will do with a kidney stone. Personaly I beleive the medical community sends misinformation with anything that doesn’t MAKE THEM MONEY. shockwave lithotripsy therapy costs $8,000.00+ and a coke cost $.75

  5. Sharon

    I have been plagued with kidney stones since my 30’s. I am now 65 and passing a stone or trying too. My sister drinks a six pack of Diet Pepsi a day. She has never had a kidney stone. My brother & I, rarely drink any soda and we both get them frequently. It defies science but there must be something to this.

  6. Tamara

    I love all these comments. I’ve done the coke/asparagus treatment with success. These comments just prove, doctors, nurses, people, should not “text book” a person. We are all so very different. The “text book” is a good place to start, but please keep an open mind and listen to our body, doctors truly.. listen without forming your reply while your patient is talking. Wishing you all good health.

    • jharris

      Hi Tamara,
      Sounds like you had a negative doc visit. Sorry to hear that. Thanks for writing.
      Best, Jill

    • Rod Hamp

      jharris, typical response from someone in the medical community

  7. Lisa Vinson

    I am 45 years old and I have MSKD. I pass debris daily and larger stones frequently. I started “noticing” my disease from symptoms that worsened in my 30’s and became life altering after the pregnancy of my last child (which is when my diagnosis was confirmed.) Since that time, I have tried many things. Long term antibiotic therapy, Flomax, Rocephin injections in combination with antibiotics…and many home remedies such as cranberry juice, concentrated cranberry, lemonade, gallons of water, cider vinegar, soda, and diet soda. Out of all of these things I have “tried” the ONLY thing that seems to work (NOT with stone formation but with aiding a stone to “move” out, once it drops) is soda or diet soda. My family argues, my doctors argue, science argues, but I KNOW MY body. I do not drink sodas normally but when I am in agony and a stone feels “stuck” and my urine is not flowing (no matter how much water I drink) and my kidney is spasming…I pop a top of one soda and sip on it…my urine begins to flow and the stone passes (usually within a few hours.) My husband used to think I was nuts but now sees…it works (on me.) I wish I knew WHY it works because I don’t see much evidence supporting it. I wonder how many other people it might help? I don’t add asparagus because the soda alone, works. And btw Cranberry juice…is for the birds (I get SO sick of people trying to force me to drink it…been there, done that, for a stone builder…it shows no instant relief.)

    • Julie

      How much coke did u have to drink? And was there a time to drink a certain amount?

  8. Mark goza

    I found out the hard way that not only dark sodas are not good for acid reflux. I myself was having bad kidney stones, I cant afford to have the stones tested but I started drinking more water, I never drank water that much, I take depakote for bipolar and found out I was dehydrated, before I started taking depakote. Tea and coffee I believe makes me have stones. Is there any truth in that?

  9. Brad

    I tried this method, except I eat steamed asparagus BEFORE drinking the Coke. Eat the asparagus first, wait about 30 minutes, and then I drink 2-3 cans of room temperature or maybe slightly warmer if possible Coke. Not diet Coke either. Then I drink water after than and just wait until I have to pee extremely bad. I do this “cleanse” about once every 6 months or so. I don’t drink Coke normally outside of that. Maybe once or twice a month if that. Mainly water. Since I started doing this, I’ve never gotten a stone in 12 years. Not sure if it truly works or not, but as long as I’m not getting a stone, it’s not doing any harm.

  10. chris

    this is crazy.. I can tell you 100% that my abuse of cola aka Pepsi an coke is what gave me my stones.. not once but 2x I had a 8mm stone for months and months I suffered threw it. both times it was when I came off keto and starting drinking soda this time I am using flomax from the last time drinking lemon water tryin to pass this one it must be smaller because I feel it in my Lower area and it was in my kidney area not more then 2 days ago last time it was months of pain this so far has been days.. on and off lets hope it passes.. but please stay off the sodas high fructose corn syrup is poison they do not use sugar anymore like the rest of the world does.


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