7 Kidney Disease Symptoms You Should Know, According to Experts

Your kidneys remove waste and excess fluid from your body by producing urine. “If the kidneys slow down or do not work well, then fluid can be retained,” says Mateo Ledezma, M.D., a nephrologist with Kaiser Permanente. “This can result in persistent swelling in tissue.” This type of swelling is called edema.

When more fluid is stuck in your tissues, less is being flushed out—meaning you may be peeing less than usual. If you notice you’re drinking the same amount you normally do, but urinating less frequently, it may be worth bringing up with your doctor.

“Part of the function of the kidneys is to help regulate a person’s hemoglobin level,” says Ledezma. Hemoglobin is a protein in your red blood cells that helps circulate oxygen throughout the body. When something goes wrong with your kidneys, your hemoglobin levels can drop and you can become anemic—making you feel tired and weak.

When waste builds up in your system because your kidneys aren’t filtering it out, it can start to mess with other parts of your body. This can lead to nausea, vomiting, and loss of appetite and just generally make you feel sick.

Waste build-up can also affect your brain, causing you to feel like you can’t think clearly. Pay attention to symptoms like forgetfulness, trouble concentrating, confusion, and brain fog, especially if they’re out of character for you.

Once your kidneys are damaged, they can’t effectively regulate your blood pressure. And this causes an unfortunate cycle. The force of your blood pounding against your vessels stretches them, causing further damage by scarring and weakening the blood vessels in your kidneys.

“If your kidney damage is causing a build-up of potassium, you might notice an abnormal heartbeat,” says Allen. Your heartbeat might seem fast or irregular, or you may feel like your heart is fluttering.