However, swelling is not specific to kidney disease. Standing or sitting for long periods, certain medications, venous circulation problems, heart failure, and liver disease can also cause it.
The pattern and accompanying symptoms matter.
Persistent swelling that develops without an obvious explanation deserves medical attention, particularly if it occurs alongside foamy urine, reduced urination, or high blood pressure.
Sudden swelling in one leg, especially when accompanied by pain, warmth, or redness, requires urgent assessment because a blood clot may be responsible. Swelling accompanied by chest pain or shortness of breath may indicate a medical emergency.
Do not attempt to treat unexplained swelling by drastically restricting water intake or taking diuretics without medical advice. The correct treatment depends on the underlying cause.
5. Puffiness Around the Eyes
Another possible sign of kidney-related problems is swelling around the eyes, especially upon waking.
This can happen when fluid accumulates in the tissues surrounding the eyes. In some kidney conditions, substantial amounts of protein leak into the urine, reducing the concentration of albumin in the blood and allowing fluid to move into surrounding tissues.
The resulting puffiness may be particularly noticeable in the morning, although its appearance varies.
It is important to understand that swollen eyelids are common and have many possible explanations. Allergies, sinus problems, eye irritation, lack of sleep, and other conditions can produce similar symptoms.
The concern becomes greater when persistent puffiness occurs together with swelling in the feet or ankles, unusually foamy urine, or unexplained weight gain.
A clinician may recommend urine testing to check for protein, blood tests to evaluate kidney function, and additional investigations depending on the findings.
If the swelling is sudden and affects the lips or tongue, or causes difficulty breathing, seek emergency medical assistance because a severe allergic reaction may be responsible.
6. Persistent Fatigue and Low Energy
Feeling tired after a demanding day is normal. Persistent exhaustion that does not improve with adequate rest, however, deserves attention.
The kidneys do more than filter waste. They also produce erythropoietin, a hormone that signals the bone marrow to make red blood cells.
Red blood cells carry oxygen throughout the body. When advanced kidney disease reduces erythropoietin production, a person may develop anemia, meaning the blood has a reduced capacity to carry oxygen.
Anemia can cause fatigue, weakness, reduced exercise tolerance, dizziness, headaches, and difficulty concentrating.
Waste products that accumulate as kidney function declines may also contribute to feeling generally unwell. Sleep disturbances, inflammation, poor appetite, and other complications can further reduce energy levels.
Some people describe the experience as feeling tired all day despite sleeping for an adequate number of hours. Others notice that familiar tasks, such as climbing stairs, walking quickly, or completing household chores, suddenly require more effort.
Nevertheless, fatigue is one of the most nonspecific symptoms in medicine. It can result from anemia unrelated to kidney disease, thyroid disorders, nutritional deficiencies, sleep apnea, depression, infections, or many other conditions.
If fatigue persists for several weeks, interferes with daily activities, or occurs alongside other possible kidney symptoms, a medical assessment is appropriate.
Blood tests can help determine whether anemia or impaired kidney function is present. Treatment depends on the cause rather than on fatigue alone.
7. High Blood Pressure That Is Difficult to Control
High blood pressure is both a major risk factor for kidney disease and a possible consequence of it.
This relationship can create a harmful cycle. Persistently elevated blood pressure can damage the small blood vessels inside the kidneys, reducing their ability to filter blood efficiently. Damaged kidneys may then retain more sodium and water and produce hormonal signals that raise blood pressure further.
Over time, these changes can reinforce one another.
The difficulty is that high blood pressure often causes no noticeable symptoms. A person may feel perfectly normal while blood pressure remains elevated for months or years.
This is why regular measurement matters, even when there is no headache, dizziness, or other obvious warning sign.
People who already have hypertension should follow their prescribed treatment plan, monitor their readings as advised, and attend recommended follow-up appointments.
If blood pressure remains above the target established by a clinician despite taking medication, it is worth discussing whether kidney function should be reassessed.
A clinician may recommend blood tests for creatinine and estimated glomerular filtration rate, as well as urine testing for albumin.
Blood pressure readings around 180/120 mmHg or higher require immediate attention. If such a reading is accompanied by chest pain, shortness of breath, confusion, weakness, vision changes, or severe neurological symptoms, call emergency services. Even without those symptoms, repeat the measurement after a brief rest and seek urgent medical guidance if it remains severely elevated.
Controlling blood pressure can help protect the kidneys and reduce the risk of cardiovascular complications.
8. Unexplained Nausea or Loss of Appetite
Changes in appetite may seem unrelated to the kidneys, but they can occur when kidney disease becomes more advanced.
As kidney function declines, waste products that would normally be removed from the bloodstream can accumulate. These changes may affect the digestive system and contribute to nausea, reduced appetite, or an unpleasant taste in the mouth.
Some people report feeling full quickly, finding familiar foods less appealing, or experiencing nausea that is difficult to explain.
In more advanced disease, these symptoms may occur alongside fatigue, itching, swelling, or changes in mental clarity.
However, nausea and appetite loss are common symptoms with many possible causes, including gastrointestinal illness, medication side effects, pregnancy, infections, and metabolic disorders.
They are not reliable indicators of early kidney disease by themselves.
Persistent nausea, repeated vomiting, or a prolonged inability to eat or drink adequately should be assessed by a healthcare professional. Dehydration can itself cause acute kidney injury, particularly in people who are already vulnerable.
If vomiting is severe, urine output falls substantially, or a person becomes confused or unusually drowsy, urgent evaluation is necessary.
9. Itching That Has No Obvious Explanation
Persistent itching can occur in people with advanced chronic kidney disease, particularly when complications associated with reduced kidney function develop.
The mechanism is complex and may involve inflammation, changes in mineral balance, altered immune signaling, and other factors. It is not simply a matter of waste products accumulating directly beneath the skin.
Some people experience generalized itching without a visible rash. Others notice discomfort that becomes worse at night or interferes with sleep.
Dry skin can also contribute, especially in older adults or people living in environments with low humidity.
Itching alone is not a strong indicator of early kidney disease. More common explanations include eczema, allergies, medication reactions, liver or thyroid disorders, and other skin conditions.
However, persistent generalized itching that does not improve with ordinary skin care deserves investigation, especially if other symptoms are present.
A clinician can assess the skin, review medications, and determine whether blood tests for kidney function, liver function, or other conditions are appropriate.
Avoid assuming that itching is caused by kidney disease or starting supplements intended to alter mineral levels without medical guidance.