Kidney Stones: What Are They?

01/30/2023 | 5 min. read

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Kidney stones may be small, but they can cause big problems. Healthy Directions is here to cover everything you need to know about kidney stones, including risk factors, types, symptoms, treatments, and prevention.

What Are Kidney Stones?

A kidney stone is a hard deposit that’s formed from chemicals in the urine. Kidney stones are quite prevalent, and it’s estimated that one in ten people will experience a kidney stone at some point in their lives.

However, some people are more prone to developing kidney stones than others based on family history, personal history, diet, weight, and other medical conditions.

What Are the Different Types of Kidney Stones?

There are four different types of kidney stones: calcium oxalate, uric acid, struvite, and cystine. Here’s what you need to know about each type:

Calcium oxalate

This type of kidney stone forms when calcium interacts with oxalate in the urine. Risk increases when there are excesses in the urine of calcium or oxalate, which is abundant in some fruits and vegetables as well as nuts and chocolate. Calcium oxalate stones are the most common type of kidney stone.

Uric acid

This type of kidney stone forms due to excess amounts of uric acid in the body. Uric acid is a waste product produced by the body during the breakdown of natural chemicals called purines. Uric acid is supposed to leave the body through the urine, but excess amounts may get left behind and eventually combine with other substances in your body to form a kidney stone.

Uric acid kidney stones tend to run in families, which means genetic factors may be involved in their formation.


This type of kidney stone forms as a result of a urinary tract infection. Struvite kidney stones are less common than some of the other types. However, they can prove to be fast-growing and most problematic.


This type of kidney stone forms when the body produces excess amounts of the amino acid cystine. This amino acid then gets into the urine and can accumulate into a stone.

Cystine kidney stones are considered to be quite rare as they only occur in those with a disorder known as cystinuria, an inherited genetic disorder.

How To Know If You Have Kidney Stones?

It can be challenging to determine whether you’re dealing with kidney stones or other medical issues. Here are some common symptoms of kidney stones to look out for:

  • Discomfort in the lower side and back
  • Pink, red, or brown urine
  • Cloudy or smelly urine
  • Frequent urination
  • Nausea
  • Vomiting
  • Fever

When To See a Doctor About Kidney Stones?

While it may be possible to pass a kidney stone on your own, large kidney stones may require medical treatment. Schedule an appointment with your primary care provider if you have any concerning and recurring symptoms.

Seek immediate medical attention if you’re experiencing any of these severe symptoms:

  • Severe discomfort
  • Nausea and vomiting
  • Fever and chills
  • Blood in the urine
  • Difficulty urinating

Your doctor may run a variety of diagnostic tests to determine whether or not you’re dealing with kidney stones and how large they are.

For example, your doctor may order a blood test to analyze the calcium and uric acid content in your body. Your doctor may also order a urine test to analyze your body’s production of stone-forming minerals and stone-preventing substances.

Finally, your doctor may order imaging tests in the form of CT scans or X-rays to locate any kidney stones that are currently trapped in your urinary tract.

How Are Kidney Stones Treated?

The course of treatment for kidney stones is dependent on their size. Small kidney stones that are causing minimal symptoms can usually be passed naturally.

However, your doctor may recommend increasing your intake of fluids to help flush it out of your system. They may also recommend that you take pain relievers like ibuprofen, acetaminophen, or naproxen sodium for any discomfort you’re experiencing.

Finally, they may prescribe medication in the form of an alpha-blocker to relax the muscles in your ureter so that you can pass the stone quickly and easily.

Large or otherwise problematic stones may require more invasive treatment. Here are some common methods of treatment for kidney stones that are too large to pass naturally:

Extracorporeal Shock Wave Lithotripsy (ESWL)

The first course of treatment involves a procedure known as extracorporeal shock wave lithotripsy or ESWL.

This procedure uses the vibrations from sound waves to break up your kidney stone into smaller pieces that can then be passed in your urine. This is usually an outpatient procedure that lasts less than an hour and may require some level of sedation.

Percutaneous Nephrolithotomy

If ESWL was not successful, the second source of treatment involves a procedure known as percutaneous nephrolithotomy. In this procedure, small incisions are made in your back and compact surgical instruments are used to remove the kidney stone.

Since this is a surgical procedure, you will be put under general anesthesia and stay in the hospital for a day or two to recover.


If you have a smaller stone, your doctor may be able to access it and either remove it or break it up by inserting a scope equipped with a camera into your urethra and through your bladder. This procedure may require either general or local anesthesia.

How to Prevent Kidney Stones?

While it may not be possible to prevent kidney stones completely, there are some things you can do to reduce your risk:

  • Stay hydrated so that you produce and pass enough urine
  • Adjust your diet and reduce your intake of salt, animal proteins, and oxalate-rich foods
  • Consider taking 1/4-1/2 cup of lemon juice in water a day.
  • Avoid taking calcium supplements and instead choose supplements that support optimal calcium absorption


While most kidney stones aren’t considered a medical emergency, they can still be extremely uncomfortable. Furthermore, some kidney stones will require medical treatment.

As a result, it’s essential to understand what kidney stones are, how they’re formed, and how you can prevent them from forming in the first place.


Kidney Stones - Symptoms, Causes, Types, and Treatment | National Kidney Foundation

Uric Acid Stones | Cleveland Clinic

Diagnosis and Treatment of Kidney Stones | Mayo Clinic

Healthy Directions Staff Editor