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Neutra-Phos-K Side Effects

Generic Name: potassium phosphate

Note: This document contains side effect information about potassium phosphate. Some of the dosage forms listed on this page may not apply to the brand name Neutra-Phos-K.

For the Consumer

Applies to potassium phosphate: intravenous solution

Along with its needed effects, potassium phosphate (the active ingredient contained in Neutra-Phos-K) may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor or nurse immediately if any of the following side effects occur while taking potassium phosphate:

Incidence not known
  • Burning, crawling, itching, numbness, prickling, "pins and needles", or tingling feelings
  • chest pain or discomfort
  • confusion
  • dizziness, faintness, or lightheadedness when getting up suddenly from a lying or sitting position
  • fast, slow, or irregular heartbeat
  • muscle cramps in the hands, arms, feet, legs, or face
  • no muscle tone or movement
  • numbness and tingling around the mouth, fingertips, or feet
  • pounding or rapid pulse
  • shortness of breath
  • unusual tiredness or weakness
  • weakness and heaviness of the legs

For Healthcare Professionals

Applies to potassium phosphate: intravenous solution, oral powder for reconstitution


Signs of hyperkalemia include muscle weakness, frank skeletal muscle and diaphragm paralysis, peaked T waves on the ECG, and cardiac arrhythmias. If toxicity is suspected or documented, potassium should be stopped immediately. While monitoring the ECG, a combination of dextrose and insulin in a ratio of 3 g of dextrose for every 1 unit of insulin may be administered. Sodium bicarbonate 50 to 100 mEq and calcium gluconate 10% intravenously may be helpful if acidosis is present. Potassium-binding resins or dialysis may be necessary in serious cases.

Hyperkalemia is significantly more likely in elderly patients with uremia who receive high doses.

In patients with renal failure, other factors that may cause hyperkalemia include defects in the renin-angiotensin-aldosterone axis, tubular defects in potassium secretion, intra- to extracellular potassium shifts due to metabolic acidosis, and possible high potassium loads from underlying disease states (such as rhabdomyolysis, hemolysis, gastrointestinal bleeding, etc.).

Renal failure is the most common cause of hyperphosphatemia. Other factors that may contribute to hyperphosphatemia in patients with renal insufficiency include high phosphorus intake, and rarely, hypoparathyroidism or acromegaly.

When severe, hyperphosphatemia may reduce the extracellular concentration of ionized calcium (increasing the risk of tetany) and increase the risk of extraosseous calcification.[Ref]

Metabolic side effects have been reported the most frequently and have usually resulted from hyperkalemia and/or hyperphosphatemia. They have included muscle weakness, frank skeletal muscle and diaphragm paralysis, peaked T waves on the ECG, life-threatening cardiac arrhythmias and an increased risk of extraosseous calcification.

While the most common cause of hypokalemia in patients with liver cirrhosis is diuretic therapy, other causes include low dietary intake, enhanced renal loss due to hyperaldosteronism, magnesium deficiency, and accelerated gastrointestinal losses. Hypophosphatemia may be associated with malnutrition in some patients with alcoholic liver disease.[Ref]


Gastrointestinal side effects have included diarrhea, nausea, stomach pains, and vomiting.[Ref]


Cardiovascular side effects have included fast or irregular heartbeat, dyspnea, lower extremity edema, and unusual weight gain.[Ref]

Nervous system

Nervous system side effects have included headaches, dizziness, thirst, mental confusion, seizures, weakness or heaviness of the legs, muscle cramps, numbness, tingling, and perioral tingling.[Ref]


1. Wilson J, Braunwald E, Isselbacher K, Petersdorf R, Martin J, Fauci A, Root R "Harrison's Principles of Internal Medicine, 12th Edition." McGraw-Hill, Inc., Health Professions Division, New York 1 (1991): 1938

2. "Product Information. K-Phos Neutral (potassium phosphate)." Beach Pharmaceuticals, Tampa, FL.

Some side effects of Neutra-Phos-K may not be reported. Always consult your doctor or healthcare specialist for medical advice. You may also report side effects to the FDA.

Disclaimer: Every effort has been made to ensure that the information provided is accurate, up-to-date and complete, but no guarantee is made to that effect. In addition, the drug information contained herein may be time sensitive and should not be utilized as a reference resource beyond the date hereof. This material does not endorse drugs, diagnose patients, or recommend therapy. This information is a reference resource designed as supplement to, and not a substitute for, the expertise, skill , knowledge, and judgement of healthcare practitioners in patient care. The absence of a warning for a given drug or combination thereof in no way should be construed to indicate safety, effectiveness, or appropriateness for any given patient. does not assume any responsibility for any aspect of healthcare administered with the aid of materials provided. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the substances you are taking, check with your doctor, nurse, or pharmacist.