Ask the Pharmacist

Q) I recently went through a brutal week as I suffered through the passing of a kidney stone. What can you tell me about them and what can I do to prevent this from happening again?

A) Kidney stones really, like REALLY, hurt. The level of pain has been described as unbearable to the point that some of the affected individuals thought that they were dying! Recently England’s National Health Service (essentially Health Canada’s equivalent) listed the 20 most painful conditions and kidney stones were mentioned prominently alongside such other luminaries as broken bones and cluster headaches. In fact, they received a special mention as being one of the few entries on the list (which is more than a little surprising) that could potentially be life threatening and therefore require urgent medical attention. Kidney stones are also very common.

One in six people will develop them at some point in their life. It used to be predominantly a male disease (happening about twice as often in men) but that has levelled out over time so that the risk of being affected is pretty much the same between males and females.

If you’ve had stones in the past, you have about a 50% chance of having it occur again which is a really high recurrence rate. Kidney stones are formed from some of the minerals and salts that are dissolved in our urine. When our urine has levels of these salts that are too high for them to remain “in solution” (refer to your grade 9 science notes regarding saturation and other such enthralling topics!), they recrystallize to a solid in the form of a stone. They can start small but can grow quite large in size. They may stay in the kidneys and not cause any problems or induce any pain whatsoever. However, they may also travel down the ureter, which is the tube that connects the kidneys to our bladder, which is where problems often result.

If the stone actually reaches the bladder, there is a chance the stone may be “passed” out of our body in a stream of urine thus resolving the issue. However, the stone may become lodged within the ureter, which is when the problems arise. This is when you get the pain and perhaps a blockage of flow of urine from the kidneys. Symptoms of kidney stones include:

· Blood in the urine
· A burning type of pain when urinating
· Cloudy and or smelly urine
. Fever and chills
· Frequent urination
· Nausea &/ or vomiting
· An intense, sharp pain in the side or back that doesn’t go away.

While the vast majority of kidney stones do not cause lasting damage, there can be complications which is why they shouldn’t be ignored, even if you are one of the lucky ones who escape relatively pain free.

If the urine cannot properly escape the body due to the obstruction caused by the kidney stone, it may build-up and put a strain on your body. Some of these complications are relatively simple to treat such as a urinary tract infection but others can be life threatening or altering such as an injury to the kidneys or sepsis which is an infection that spreads throughout the whole body.

Treatment of an active stone depends on a number of factors. If imaging finds it to be a smaller stone that is not obstructing the passage of urine, doctors will often leave them alone to see if you will pass it on your own. You will be encouraged to drink lots of fluids although newer advice finds this recommendation questionable as it rarely works and frequently just makes the bladder more irritated. You may be given specific medications to help such as:

· tamsulosin which helps to relax the ureter making it easier for the stone to pass
· pain relievers – NSAIDs like Advil or Toradol seem to work the best
· anti-nausea medication depending on the severity of your symptoms

Trying to relax is huge as well. Experts advise trying meditation and taking lots of hot baths to help with this. It may take weeks for the stone to pass. However if it doesn’t (sometimes depending on the severity of symptoms a doctor may wait up to 4 to 6 weeks ) or if the pain is too severe or the kidneys are showing signs of strain, surgery may be booked.

Surgery is relatively simple with either very small incisions or no cuts at all and one should be able to return to life as per normal shortly thereafter. Surgical techniques include:

· Shock wave lithotripsy – shock waves are focussed on the stone in order to break it into smaller pieces
· Ureteroscopy – where a small telescope is inserted into the bladder allowing the urologist to see the stones and grab them with a basket-like device
· Percutaneous nephrolithotomy – where a 1/2 inch incision is made and an instrument is used to break up the stones and suction out the pieces.

The key take home for stones is that they are best avoided in the first place and that is something most of us can largely control. The key recommendation is to stay hydrated, something that can be hard to do in the heat, which is why stones occur far more commonly in the summer.

Expert advice recommends drinking 96 ounces of water a day (which is almost 3 litres!!) throughout the day rather than large amounts at once. Cutting back on animal protein (read meat and dairy) and following a low sodium diet also can reduce your risk. One should also eat oxalate-rich foods in moderation. Examples of such foods are s beets, chocolate, rhubarb, nuts, berries and greens.

Since some of these are also considered healthy food options, we don’t suggest avoiding them but also not to over indulge on them either. It is best to pair them with calcium from your diet, although ideally not from dairy so try kale, edamame, almonds, soy milk, tofu…, which binds the oxalate in the gut and excretes it as waste rather than having it accumulate in the urine. These basic recommendations work for all types of stones.

Sometimes doctors will send your stone away to have it analyzed which may lead to more specific tips depending upon what the stone is composed of. Calcium stones represent the most common type of stone (80% of all cases) with calcium oxalate being far more common than calcium phosphate. These seem to form for reasons other than having too much calcium dissolved in your urine. Uric acid stones occur about 5-10% of the time with the rest being either struvite stones (related to chronic bladder infections) and cysteine stones. One last note on the prevention front.

There is new research indicating that an innocuous diabetic drug known as empagliflozin decreased the risk of having a kidney by almost 40% over a 15 year period in type 2 diabetics who took the drug. This may lead to a change in prevention protocols not only for diabetics who are prone to stones but quite possibly in non-diabetics as well. For more information about this or any other health related questions, contact your pharmacist.