Dialysis is a life-sustaining treatment for individuals whose kidneys have failed, removing excess fluid, waste, and toxins from the blood. This function is achieved either through hemodialysis (HD), which uses an external machine to filter the blood, or peritoneal dialysis (PD), which uses the abdominal lining as a natural filter. Since dialysis cannot perfectly replicate the continuous function of healthy kidneys, a strict regimen of self-care is necessary. Adhering to these limitations maximizes the effectiveness of the treatment and prevents serious complications.
Strict Fluid and Dietary Limits
Dialysis patients must severely restrict consumption because the body can no longer efficiently excrete the byproducts of food and drink. Uncontrolled fluid intake is particularly hazardous, as the kidneys no longer produce urine. This leads to fluid overload, causing high blood pressure, swelling (edema), and severe strain on the heart, increasing the risk of heart failure and fluid accumulation in the lungs. Intake must be carefully monitored between treatments, making a “fluid allowance” a daily consideration.
Beyond fluid, several minerals and electrolytes that healthy kidneys regulate become concentrated to dangerous levels. High potassium (hyperkalemia) is a major concern because this electrolyte directly affects heart muscle function. Consuming high-potassium foods like bananas, oranges, tomatoes, and potatoes can trigger life-threatening heart arrhythmias.
Phosphorus, found in many protein-rich foods, dairy, nuts, and dark colas, also builds up in the blood. When phosphorus levels rise unchecked, it pulls calcium from the bones, causing them to become weak and brittle. This imbalance also leads to calcification of soft tissues and blood vessels, accelerating the risk of cardiovascular disease. Patients must strictly limit high-phosphorus foods and take specialized medications called phosphate binders with meals.
Sodium restriction is necessary, as excess salt intake directly contributes to fluid retention and high blood pressure. Sodium causes intense thirst, making it nearly impossible for patients to stay within their fluid allowance. Managing sodium, often found hidden in processed foods, is directly tied to managing fluid volume and preventing interdialytic weight gain.
Medication and Over the Counter Restrictions
A dialysis patient cannot safely take many common over-the-counter (OTC) medications and supplements, which are typically filtered and cleared by healthy kidneys. Nonsteroidal Anti-inflammatory Drugs (NSAIDs), such as ibuprofen and naproxen, are strictly prohibited because they can severely reduce any remaining kidney function. NSAIDs can also significantly increase the risk of gastrointestinal bleeding, a risk often heightened by other medications taken for kidney disease.
Certain mineral-containing antacids and laxatives must also be avoided due to the risk of mineral accumulation. Products containing magnesium or aluminum are particularly hazardous because the failing kidneys cannot excrete them, leading to toxicity. Accumulation can cause severe central nervous system depression or neurological issues, including dialysis-associated encephalopathy.
Herbal supplements and high-dose vitamins require strict physician approval before use. The lack of federal regulation means these products often contain unknown ingredients, including high levels of restricted minerals like potassium or phosphorus, which can lead to toxic buildup. Fat-soluble vitamins like Vitamin A can accumulate in the body to harmful levels.
Patients must also exercise caution with diagnostic procedures involving intravenous contrast dyes, such as those used in CT scans. While modern contrast agents are generally considered safe for chronic dialysis patients, they still carry an osmotic load that can cause fluid shifts. The procedure requires careful coordination with the dialysis unit to ensure the patient receives a dialysis session shortly after the test to clear the contrast and manage the extra fluid volume.
Physical and Lifestyle Limitations
Certain physical activities and lifestyle choices become restricted primarily to protect the vascular access site, which is the lifeline for hemodialysis patients. Patients with an arteriovenous fistula or graft cannot allow blood pressure cuffs or intravenous lines to be used on the access arm. They must avoid heavy lifting—generally anything over ten pounds—and refrain from wearing tight clothing or jewelry on that arm. These precautions are essential to prevent compression, damage, or clotting of the access site.
Water exposure also introduces a significant infection risk, especially for those on peritoneal dialysis (PD) with a catheter exit site in the abdomen. PD patients must strictly avoid submerging their catheter site in potentially contaminated water sources like public swimming pools, hot tubs, lakes, or rivers. The risk of bacteria entering the catheter and causing peritonitis, a serious abdominal infection, is too high.
Spontaneous travel is generally impossible because a patient cannot simply skip their essential treatments. Hemodialysis patients must pre-arrange “transient dialysis” sessions at a facility near their destination, a process that requires submitting medical records and coordinating appointments often six to eight weeks in advance. Peritoneal dialysis patients also require weeks of lead time to arrange for the delivery of the specialized dialysate solution and equipment to their travel location.
Finally, a patient cannot simply decide to skip a scheduled dialysis treatment, as this directly leads to a dangerous accumulation of toxins and fluid. Missing even one session causes waste products like urea and creatinine to build up, leading to uremia. The buildup of excess fluid and high potassium levels can rapidly trigger severe complications, including pulmonary edema and fatal cardiac arrhythmias.