Nocturia can also be associated with diabetes, an enlarged prostate, overactive bladder, sleep apnea, heart failure, and medications such as diuretics.
The important consideration is whether the change is persistent, unexplained, or accompanied by other symptoms.
If nighttime urination has recently increased, discussing it with a healthcare professional can help identify the cause.
6. Foamy or Excessively Bubbly Urine
Occasionally seeing bubbles in the toilet is not necessarily a problem.
Urine can appear bubbly when it hits the water quickly, when the toilet contains cleaning products, or when the urine is concentrated.
However, persistent foamy urine may sometimes indicate proteinuria, which means an abnormal amount of protein is present in the urine.
Healthy kidneys normally prevent most blood proteins, especially albumin, from passing into the urine.
When the kidney's filtering structures become damaged, protein can leak through and enter the urine.
Some people describe the urine as looking unusually frothy, with foam that takes longer than usual to disappear.
Proteinuria can be an early indicator of kidney damage, particularly in people with diabetes or high blood pressure.
However, appearance alone cannot confirm protein leakage. A urine albumin-to-creatinine ratio (uACR) test is commonly used to detect abnormal albumin levels.
Persistent foamy urine should be discussed with a healthcare professional, especially when accompanied by swelling or other urinary changes.
7. Blood in the Urine
Blood in the urine is known as hematuria.
It may make urine appear pink, red, brown, or tea-colored. In some cases, the amount of blood is too small to see and can only be detected through laboratory testing.
Blood may enter the urine when the kidney's filtering structures, urinary tract, or surrounding tissues become damaged.
Certain kidney conditions, including glomerulonephritis, can cause blood to leak into the urine.
However, kidney stones, urinary tract infections, bladder conditions, prostate problems, injuries, and some cancers can also cause hematuria.
Even a single episode of visible blood in the urine should be medically evaluated.
It is particularly important not to dismiss the symptom simply because it disappears. Some causes of blood in the urine require timely diagnosis and treatment.
If blood in the urine occurs alongside severe pain, fever, difficulty urinating, or blood clots, seek urgent medical care.
8. Persistent Itching Without an Obvious Cause
Unexplained itching can sometimes occur in people with advanced chronic kidney disease.
This condition is often called chronic kidney disease-associated pruritus.
When kidney function becomes significantly impaired, waste products and changes in mineral balance can contribute to disturbances in the skin and nervous system.
Inflammation, abnormal calcium and phosphate regulation, and changes in nerve signaling may also play a role.
The itching may affect the arms, legs, back, chest, or other areas of the body. Some people experience widespread discomfort, while others notice symptoms in specific locations.
In certain cases, itching becomes more noticeable at night and interferes with sleep.
Importantly, kidney-related itching does not always involve a visible rash.
However, dry skin, eczema, allergies, insect bites, liver conditions, thyroid disorders, and medication reactions are much more common explanations for itching in many people.
Persistent itching that cannot be explained by ordinary skin conditions deserves medical assessment, especially if it occurs with fatigue, swelling, or changes in urination.
9. Dry, Flaky, or Unusually Irritated Skin
The kidneys help regulate the balance of minerals and fluids throughout the body.
When kidney function becomes severely impaired, these regulatory processes may be disrupted.
Some people with advanced kidney disease develop dry, rough, flaky skin. This may occur alongside persistent itching.
Changes in calcium and phosphate balance, inflammation, and other metabolic disturbances can contribute to skin discomfort.
People may notice that their skin feels tight, becomes irritated easily, or develops small areas of scaling.
However, dry skin is extremely common and is often caused by cold weather, frequent bathing, harsh soaps, dehydration, aging, or skin conditions.
Dry skin alone is not a dependable warning sign of kidney disease.
If it is persistent and accompanied by other unexplained symptoms, a healthcare professional can help determine whether further testing is needed.
10. Muscle Cramps, Especially in the Legs
Sudden muscle cramps can be painful and disruptive, particularly at night.
People with advanced kidney disease may experience muscle cramps because of changes in electrolyte levels, fluid balance, nerve function, or muscle metabolism.
Electrolytes such as potassium, calcium, sodium, and magnesium are essential for normal muscle contraction and relaxation.
When these substances become imbalanced, muscles may become more prone to involuntary contractions.
Some people experience cramps in their calves, feet, or thighs. Others report twitching or uncomfortable muscle sensations.
However, muscle cramps can also result from exercise, dehydration, prolonged sitting, pregnancy, nerve compression, and certain medications.
People with kidney disease should not automatically take electrolyte supplements to treat cramps. Excess potassium or magnesium can be dangerous when kidney function is impaired.
Persistent or severe cramps should be discussed with a healthcare professional, who may recommend blood tests to assess electrolyte levels and kidney function.
11. Shortness of Breath
Breathlessness can sometimes develop when kidney disease becomes advanced.
One possible cause is fluid accumulation. If the kidneys cannot remove enough excess fluid, it may build up in the body and, in serious cases, affect the lungs.
This can make breathing difficult, particularly when lying flat or during physical activity.
Another possible cause is anemia. Reduced red blood cell production can decrease the amount of oxygen carried through the bloodstream, leaving a person unusually breathless during everyday activities.
However, shortness of breath is a symptom that should never be casually attributed to kidney disease without evaluation.
Heart disease, lung conditions, blood clots, infections, and other medical emergencies can also cause breathing difficulties.
Sudden or severe shortness of breath, chest pain, fainting, blue lips, or difficulty breathing while resting requires emergency medical attention.
12. Loss of Appetite
People with advanced kidney disease may experience a reduced appetite.
As kidney function declines, waste products and metabolic changes can affect the digestive system and the way food tastes and smells.
Some individuals feel full quickly, become nauseated when thinking about food, or lose interest in meals they previously enjoyed.