Kidney Stones: Symptoms, Causes, and Prevention

Kidney stone pain is often described as one of the most intense experiences a person can have. These hard mineral deposits form in the kidneys and can cause excruciating discomfort as they travel through the urinary tract. According to the Mayo Clinic, kidney stones form when your urine contains more crystal-forming substances than the fluid can dilute, creating an environment where stones develop. Understanding the symptoms, knowing when to seek emergency care, and implementing prevention strategies can help you protect your kidney health.

What Are Kidney Stones?

Kidney stones, also called renal calculi, nephrolithiasis, or urolithiasis, are hard deposits made of minerals and salts that form inside your kidneys. They can range in size from a grain of sand to a golf ball, though most are small enough to pass through the urinary tract.

The most common types of kidney stones include:

• Calcium oxalate stones: The most common type, formed when calcium combines with oxalate, a substance made by your liver or absorbed from foods

• Calcium phosphate stones: Form when calcium combines with phosphorus, more common in people with metabolic conditions like renal tubular acidosis

• Uric acid stones: Develop when urine is too acidic, often related to high-purine diets or conditions like gout

• Struvite stones: Result from certain types of bacterial urinary tract infections

• Cystine stones: A rare type caused by a genetic disorder

Approximately 1 in 10 men and 1 in 14 women will develop kidney stones during their lifetime, making this a common urological concern.

Recognizing Kidney Stone Symptoms

A kidney stone may sit in the kidney and cause no symptoms at all. However, when a stone enters the ureter or blocks part of the kidney, obstructing urine flow to the bladder, it triggers severe symptoms.

The hallmark symptom is severe, sharp pain in the side and back, below the ribs. According to the Mayo Clinic, the pain may come in waves and may lessen if urine leaks by the blockage. As the stone travels from the kidney and down the ureter, the pain may change in location and character.

Other kidney stone symptoms include:

• Pain during urination: Burning or discomfort when passing urine

• Blood in urine (hematuria): Urine may appear pink, red, or brown

• Nausea and vomiting: Often accompanies the intense pain

• Persistent urge to urinate: Feeling the need to go frequently

• Urinating more frequently or in small amounts: Changes in urination patterns

• Fever and chills: May indicate an infection is present

• Cloudy or foul-smelling urine: Can signal infection

When Kidney Stone Pain Becomes an Emergency

Certain symptoms require immediate medical attention. Seek emergency care if you experience:

• Pain with high fever or chills: May indicate a kidney infection requiring urgent treatment

• Blood in urine with severe pain: Especially if accompanied by other symptoms

• Inability to urinate: Complete blockage requiring intervention

• Pain so severe you cannot sit still or find a comfortable position: This level of pain warrants medical evaluation

• Pain accompanied by nausea and vomiting that prevents you from keeping down fluids: Risk of dehydration

These signs may indicate a blockage or infection that requires prompt medical treatment to prevent serious complications.

What Causes Kidney Stones to Form

Kidney stones form when urine lacks substances that prevent crystals from sticking together, creating an ideal environment for stone formation. Several factors contribute to this process:

Dehydration: The most common cause. When you don't drink enough fluids, urine becomes concentrated with minerals that can crystallize. Loss of water through sweating from activities like saunas, hot yoga, or heavy exercise leads to less urine production, allowing stone-causing minerals to settle.

Diet: According to the Mayo Clinic, a diet high in protein, salt, and sugar increases your risk. Certain foods like rhubarb, beets, spinach, sweet potatoes, nuts, chocolate, and tea can contribute to stone formation.

Family history: Heredity plays a significant role. People with a family member who has had kidney stones are twice as likely to develop stones themselves.

Obesity: High body mass index, large waist size, and weight gain are contributing factors.

Certain medical conditions: Hyperparathyroidism, urinary tract infections, inflammatory bowel disease, and chronic diarrhea can increase risk.

Some medications: Certain diuretics, calcium-based antacids, and other medications may increase stone risk.

Types of Kidney Stones and Their Causes

Understanding your stone type helps guide prevention strategies:

Calcium Oxalate Stones: The most common type. High oxalate foods include peanuts, spinach, beets, Swiss chard, chocolate, and sweet potatoes. Interestingly, getting adequate calcium from food sources actually helps prevent these stones by binding oxalate in the gut.

Uric Acid Stones: Associated with high-purine diets (red meat, organ meats, shellfish), gout, and conditions causing high uric acid levels. Maintaining less acidic urine can help prevent these stones.

Struvite Stones: Caused by urinary tract infections with certain bacteria. Preventing and treating UTIs promptly is the primary prevention strategy.

Cystine Stones: Result from a genetic disorder that causes the kidneys to excrete excessive amounts of certain amino acids. Requires specialized medical management.

Diagnosis and Treatment Options

Diagnosis typically involves imaging studies (CT scan, ultrasound, or X-ray) and urine tests. Treatment depends on stone size, type, and location.

Small Stones (under 5mm): According to the Mayo Clinic, you may need nothing more than pain medication and drinking lots of water to pass a kidney stone. Most small stones pass on their own within a few weeks.

Larger Stones or Those Causing Complications:

• Shock wave lithotripsy: Uses sound waves from outside the body to break up stones so they can pass

• Ureteroscopy: A scope is passed into the ureter, and a laser fiber breaks the stone into pieces that are removed. A stent may be placed for 3-10 days

• Percutaneous nephrolithotomy: Surgery for large kidney stones, involving small instruments inserted through an incision in the back. Requires general anesthesia and overnight hospitalization

Medical Expulsive Therapy: Medications like alpha-blockers can help relax the ureter muscles and help stones pass more quickly.

Preventing Kidney Stones: Evidence-Based Strategies

Prevention is crucial since 75% of people who have one kidney stone will have another. Research-backed prevention strategies include:

Hydration is Key: The National Kidney Foundation recommends drinking 2-3 quarts (8-12 cups) of liquid per day to produce adequate urine. Research shows that hydration can prevent 50% of kidney stones. Monitor your urine color, which should be pale yellow, and increase fluids if you sweat heavily.

Manage Sodium Intake: Your chance of developing kidney stones increases when you eat more sodium. According to the Mayo Clinic, higher levels of sodium cause more calcium to be excreted into the urine. Aim for 1,500 mg of sodium or less per day. Research shows that limiting sodium to 2,300 mg can cut stone recurrence by 40-60%.

Get Adequate Calcium from Food: Despite calcium being a component of most stones, adequate calcium (1,000-1,200 mg daily) from food sources actually reduces stone risk by 34%. Calcium binds oxalate in the gut, preventing absorption. However, calcium supplements may increase risk, so dietary sources are preferred.

Increase Potassium-Rich Foods: A 2022 Mayo Clinic study found that diets higher in potassium may help avoid repeat kidney stones. Include fruits and vegetables like bananas, kiwis, grapefruits, cantaloupes, and honeydew melons.

Limit Animal Protein: Too much meat increases uric acid levels. The National Kidney Foundation recommends limiting animal protein to one serving daily.

Consider the DASH or Mediterranean Diet: Both dietary patterns are associated with fewer kidney stones due to their emphasis on fruits, vegetables, whole grains, and plant proteins.

Add Citrus: Lemon juice provides citrate, which helps prevent stone formation. Adding lemon to your water provides additional benefits.

Recurrence: Why Kidney Stones Often Come Back

The statistics are sobering: approximately 30% of people will have another stone within 5 years, and up to 75% will have a recurrence at some point. This high recurrence rate makes understanding your specific stone type and implementing personalized prevention strategies essential.

After passing or having a stone removed, your healthcare provider may recommend:

• Analysis of the stone composition to guide prevention

• 24-hour urine collection to identify risk factors

• Metabolic testing to check for underlying conditions

• Personalized dietary recommendations based on your stone type

Kidney stone prevention is different for every person. Even the same type of kidney stone can be caused by different factors, making it important to work with your doctor to develop a personalized prevention plan.

Tracking Symptoms and Dietary Patterns

Monitoring your habits can help identify patterns and reduce recurrence risk:

• Track daily fluid intake to ensure adequate hydration

• Monitor dietary sodium consumption

• Note foods that may be high in oxalate or purines

• Record any urinary symptoms

• Keep track of exercise and sweating, which affects hydration needs

This information can be valuable when working with your healthcare provider to develop an effective prevention strategy.

When to See a Doctor

Seek medical attention if you experience:

• Severe pain in your side, back, or lower abdomen

• Pain accompanied by fever, chills, nausea, or vomiting

• Blood in your urine

• Difficulty urinating

• Persistent pain that doesn't improve with over-the-counter medications

Conclusion

Kidney stones are a common but preventable condition for many people. Understanding the symptoms, from the classic severe flank pain to blood in urine and nausea, can help you recognize when medical attention is needed. While passing a stone is intensely painful, most small stones pass on their own with adequate hydration and pain management.

The key to kidney stone prevention lies in staying well-hydrated, managing sodium intake, getting adequate calcium from food sources, and following dietary patterns rich in fruits and vegetables. Since recurrence rates are high, working with your healthcare provider to understand your specific risk factors and develop a personalized prevention plan is essential. With proper attention to hydration and diet, many people can significantly reduce their risk of forming new stones.

References

1. Mayo Clinic. "Kidney stones - Symptoms and causes." 2025. https://www.mayoclinic.org/diseases-conditions/kidney-stones/symptoms-causes/syc-20355755

2. Mayo Clinic. "Kidney stones - Diagnosis and treatment." 2025. https://www.mayoclinic.org/diseases-conditions/kidney-stones/diagnosis-treatment/drc-20355759

3. National Kidney Foundation. "Kidney Stone Diet Plan and Prevention." 2025. https://www.kidney.org/kidney-topics/kidney-stone-diet-plan-and-prevention

4. National Kidney Foundation. "Eat Smart to Prevent Kidney Stones." 2025. https://www.kidney.org/kidney-topics/six-easy-ways-to-prevent-kidney-stones

5. NIDDK. "Eating, Diet, & Nutrition for Kidney Stones." National Institutes of Health. https://www.niddk.nih.gov/health-information/urologic-diseases/kidney-stones/eating-diet-nutrition

Medical Disclaimer: This article is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare provider for diagnosis and treatment recommendations. The information presented here should not be used as a substitute for professional medical advice, diagnosis, or treatment. If you have concerns about your health, please seek immediate medical attention.