By Dr. Rakhi Agarwal, M.S. (General Surgery), FAIS, FICS · Medical Director, Shree Kkasturi Medicare Pvt. Ltd. Published: 26 August 2026 · Medically reviewed: 26 August 2026

There is a particular way people arrive at casualty with a kidney stone, and you can recognise it from across the room. They cannot sit. They cannot lie down. They stand, then crouch, then walk to the wall and back, holding one side of their back. Nothing they do makes any difference and they keep trying anyway.

That restlessness is actually diagnostic. Someone with an inflamed abdomen — appendicitis, a perforation — lies very still, because movement hurts more. Someone with a stone moving down the ureter cannot find a position that helps, because the pain is coming from a tube in spasm, not from anything a posture can relieve.

Most stones, in the end, pass on their own. But three things about them are worth knowing properly: which ones will not pass, the one symptom that turns this from painful into dangerous, and the fact that having had one stone makes you roughly as likely as not to form another.

Why this region sees so many

India has what doctors informally call a stone belt, and Maharashtra sits inside it. The reason is unglamorous: heat and sweat.

In a humid coastal climate like ours, a person can lose well over a litre of fluid a day without noticing — through skin, not through urine. When fluid leaves the body that way, urine becomes concentrated. The salts dissolved in it sit closer to the point where they can no longer stay dissolved, and they begin to crystallise. Add a job that involves being outdoors, a long commute, or simply the habit of drinking less because there is no clean toilet nearby, and the risk rises further.

This is also why stone presentations rise through the summer. It is not seasonal bad luck. It is seasonal dehydration.

What it feels like

The classic attack. Pain begins suddenly in the back or side, below the ribs. It comes in waves — building to something severe, easing slightly, building again. As the stone moves downward the pain travels with it: from the loin, around the flank, into the groin, and often into the testicle or the labia. Nausea and vomiting are common. The person cannot keep still.

Other symptoms:

1. Blood in the urine — sometimes visible as pink or tea-coloured urine, often detectable only on testing

2. Burning, urgency, or the constant feeling of needing to pass urine, which typically appears when the stone has reached the lowest part of the ureter near the bladder

3. Passing urine in small amounts despite the urge

4. Sometimes, nothing at all

That last point deserves emphasis. A stone sitting quietly inside the kidney frequently causes no pain whatsoever. Large branched stones can occupy much of the kidney and slowly destroy its function over years without ever producing an attack. Pain usually begins only when a stone leaves the kidney and enters the ureter — so absence of pain is not evidence of absence of stones. These are often found by accident, on a scan done for something else.

Come to hospital the same day — and one that cannot wait at all

Fever or chills alongside stone pain is an emergency.

If a stone is blocking the ureter and the urine trapped behind it becomes infected, the kidney turns into a closed, infected space. Bacteria enter the bloodstream from there, and a patient can go from uncomfortable to seriously septic within hours. This does not respond to antibiotics alone — the blockage has to be drained. It is one of the genuine urological emergencies and it is time-critical.

Come immediately for:

1. Fever, chills or shivering with stone pain — the one above

2. Not passing urine at all

3. Pain so severe you cannot keep down fluids or medication

4. Persistent vomiting

5. Stone pain in pregnancy

6. Stone pain in someone with a single kidney, a transplanted kidney, or known kidney disease

7. Pain in both sides at once

One caution about self-diagnosis. People who have had stones before tend to recognise the pain and wait it out. Usually they are right. But flank pain can also come from appendicitis, gallbladder disease, an ovarian problem, an ectopic pregnancy, and — in an older person — a leaking aneurysm of the main abdominal artery, which can mimic renal colic closely and is lethal if missed. If the pain is different from your usual stone pain, or you are over sixty and this is the first time, be examined rather than assume.

How it is diagnosed

A urine test looks for blood and signs of infection. An ultrasound of the kidneys, ureters and bladder is usually the first scan: it involves no radiation, shows stones inside the kidney well, and — importantly — shows whether the kidney is swollen with backed-up urine, which tells us there is an obstruction even when the stone itself is hidden.

A non-contrast CT scan is the most accurate test, finding stones an ultrasound may miss, particularly in the middle part of the ureter. A plain X-ray shows calcium stones but not uric acid stones, which are invisible on it. Blood tests check kidney function and, in recurrent cases, calcium and uric acid levels.

And one request we make of every patient: if you pass a stone, keep it. Catch your urine in a strainer or a clean cloth for a few days after an attack. Sending that stone for analysis tells us what it is made of, and that single piece of information changes prevention advice more than anything else we can do. Most stones that are passed get flushed away, and the opportunity is lost.

Which stones pass by themselves?

Size is the main determinant, and the rough picture is this:

Position matters too — a stone already low down near the bladder is far more likely to pass than one stuck at the top of the ureter.

If a stone is being allowed to pass, treatment is pain relief, plenty of fluids, and sometimes a medicine that relaxes the ureter to help it along. You will usually be asked to strain your urine and to come back for a repeat scan.

There is a time limit, and it matters. A ureter that stays obstructed causes progressive damage to the kidney behind it, and after several weeks that damage can become permanent — often without pain, because the pain frequently settles once the kidney stops producing urine effectively on that side. A stone that has not passed within about four to six weeks needs to be dealt with, whether or not it still hurts. Do not treat the disappearance of pain as the end of the story without a scan confirming the stone has gone.

What treatment involves

Where a stone cannot pass, several approaches exist, and the choice depends on size, position, hardness and the kidney's condition:

1. Shock wave treatment breaks the stone from outside the body into fragments small enough to pass. No cut, but not suitable for every stone.

2. Ureteroscopy with laser passes a fine telescope up through the natural urinary passage, breaks the stone, and removes the pieces. No external incision.

3. Keyhole surgery through the back (PCNL) is used for large or branched stones inside the kidney.

4. A temporary internal stent may be placed to keep the ureter open, either before definitive treatment or afterwards. It is normal to feel some urinary urgency while a stent is in place.

5. Emergency drainage — a stent or a tube placed directly into the kidney — is what is done urgently when an obstructed kidney is infected. The stone itself is dealt with later, once the infection is controlled.

At Shree Kkasturi Medicare, we provide assessment, pain control, urine and blood testing, ultrasound, and admission for intravenous fluids and analgesia where the pain or vomiting cannot be managed at home. Definitive stone removal is carried out under urological care, and we arrange this.

Prevention — which is most of the point

Here is the number that should shape how seriously you take this section: someone who has formed one stone has roughly a one-in-two chance of forming another within the next five to ten years. Prevention is not a general health suggestion here. It is treatment for a condition you already have.

1. Water, and a way to check you are drinking enough

Most adults who form stones should aim for around 2.5 to 3 litres a day, more in summer or if you work outdoors or in a hot kitchen.

But counting bottles is unreliable. Judge it by your urine instead: it should be pale, almost colourless, through most of the day. Dark yellow urine means you were behind on fluid hours ago. This one habit does more than everything else on this list combined.

Two practical points: drink through the day rather than in large quantities at once, and include a glass at night if you tend to wake to pass urine — the long overnight gap is when urine is most concentrated.

2. Cut down on salt

This is the second biggest lever and the one people never expect. A high-salt diet makes the kidney excrete more calcium into the urine, which is exactly what you are trying to avoid.

The salt worth targeting is mostly not from the shaker: papad, pickle, namkeen and farsan, packaged snacks, instant noodles, ready masalas, processed and preserved foods, and restaurant food generally.

3. Do not cut calcium — this is the most harmful myth

Many people with stones are told to stop milk, curd and paneer. This advice is wrong and it makes things worse.

Calcium eaten with food binds to oxalate inside the intestine, so that the oxalate leaves in the stool instead of being absorbed and sent to the kidney. Cut dietary calcium and more oxalate reaches the urine, not less. Low-calcium diets are associated with more stones, not fewer — and in women, with weaker bones as an additional cost.

Calcium supplements are a separate matter and can raise risk; if one has been prescribed for you, take it with meals and mention your stone history to the prescribing doctor.

4. Moderate the high-oxalate foods — moderate, not eliminate

The main ones in our diets: spinach and other dark leafy greens, beetroot, nuts, chocolate and cocoa, soya, sweet potato, and strong tea. Tea is the one most people overlook — several strong cups a day adds up.

You do not need to give these up. Eat them in normal amounts, and eat them alongside something containing calcium — curd with the palak, milk in the tea — so the oxalate is bound in the gut rather than reaching the kidney.

5. Add citrate — nimbu paani earns its place

Citrate is the body's natural stone inhibitor. It binds calcium in the urine so it cannot form crystals. Lemon and lime are among the richest sources.

Lemon juice in your water through the day is a cheap, genuinely evidence-supported measure. Keep the sugar down — sweetened drinks work against you.

6. Go easier on animal protein and sugary drinks

Large amounts of red meat, organ meat and shellfish raise uric acid and make urine more acidic, which favours both uric acid and calcium stones. Colas in particular are worth cutting; sweetened fizzy drinks are associated with higher stone risk.

7. Do not hold urine, and manage weight and diabetes

Urine held for long periods is concentrated and stagnant. If your work makes this difficult, it is worth solving — it is a real contributor. Obesity and diabetes both independently raise stone risk.

8. If you have had a stone, get properly assessed

Anyone with recurrent stones, a stone in childhood, a family history, a single kidney, or a stone made of anything other than calcium oxalate should have a proper metabolic assessment — typically a 24-hour urine collection alongside blood tests. It identifies the specific abnormality driving your stones, and it turns general advice into advice that fits you.

Myths worth discarding

1. "Beer flushes out stones." No. Alcohol dehydrates, and increases uric acid. The passing of a stone after beer is the fluid volume, not the beer, and you could have had the same effect from water without the downside.

2. "Stop milk and paneer." Covered above — actively counterproductive.

3. "Coconut water dissolves stones." It is an excellent hydrating drink and worth having. It does not dissolve anything.

4. "No pain means no stone." Silent stones can destroy a kidney over years.

5. "I passed one, so it's finished." Roughly a one-in-two chance of another within five to ten years.

6. "Home remedies can dissolve any stone." Only uric acid stones can genuinely be dissolved, and that requires making the urine less acidic under medical supervision — not a home preparation. Calcium stones cannot be dissolved by anything taken by mouth.

Frequently asked questions

Q. How long does it take for a stone to pass? A. Small stones commonly pass within one to three weeks, sometimes sooner. A stone that has not passed in about four to six weeks needs intervention, regardless of whether it still hurts — the risk at that point is silent damage to the kidney behind the obstruction.

Q. The pain stopped on its own. Does that mean it has passed? A. Not necessarily, and this is an important trap. Pain can settle because the stone has passed — or because the obstructed kidney has stopped producing urine effectively on that side. The two feel the same. Confirm with a scan, or by having actually seen the stone.

Q. Can I drink beer to pass a stone? A. No. Water does the same job without dehydrating you afterwards or raising your uric acid.

Q. Should I stop calcium-rich food? A. No. Normal dietary calcium reduces stone risk by binding oxalate in the gut. Restricting it increases risk. This is one of the most common and most harmful pieces of advice given about stones.

Q. Is surgery always needed? A. No. The majority of stones pass without any procedure. Intervention is for stones too large to pass, stones causing obstruction, stones with infection, and stones that have not moved within a reasonable time.

Q. How do I stop them coming back? A. Fluids first — enough that your urine stays pale through the day. Then reduce salt, keep normal dietary calcium, moderate high-oxalate foods, and add lemon. If you have had more than one, have the stone analysed and get a metabolic assessment so the advice can be made specific to you.

Q. Are kidney stones hereditary? A. There is a familial tendency, partly genetic and partly shared diet and climate. A family history raises your risk and is a good reason to take the prevention measures seriously before your first stone rather than after.

Shree Kkasturi Medicare Pvt. Ltd. is a 45-bed NABH Entry Level accredited multispecialty hospital in Bhayander West, serving Mira-Bhayander since 2001, with general surgical services, 24×7 casualty, a 24×7 pathology laboratory, ultrasound, ICU and dialysis. Free ambulance pick-up is available.

Disclaimer: This article provides general health information and is not a substitute for consultation, examination or diagnosis by a qualified doctor. Severe flank pain has causes other than stones, some of them serious. If you have fever alongside stone pain, or cannot pass urine, go to a casualty department immediately.