K-Dur 20mEq (1500mg)

Pharmacology

Potassium ion is the principal intracellular cation of most body tissues. Potassium ions participate in a number of essential physiological processes including the maintenance of intracellular tonicity, the transmission of nerve impulses, the contraction of cardiac, skeletal and smooth muscle and the maintenance of normal renal function. Potassium depletion may occur whenever the rate of potassium loss exceeds the rate of potassium intake. Such depletion usually develops slowly as a consequence of prolonged therapy with oral diuretics, primary or secondary hyperaldosternism, diabetic ketoacidosis, severe diarrhea, or inadequate replacement of potassium in patients on prolonged parenteral nutrition. Potassium depletion due to these causes is usually accompanied by a concomitant deficiency of chloride and is manifested by hypokalemia and metabolic alkalosis.

K-DUR tablets contain microcrystalloids which disperse upon disintegration of the tablet. The microcrystalloids are formulated to provide a controlled release of potassium chloride. The dispersibility of the microcrystalloids and the controlled release of ions from them are intended to minimize the possibility of high local concentrations of potassium within the gastrointestinal tract.

Indications

For the treatment of patients with hypokalemia with or without metabolic alkalosis in the treatment of digitalis intoxication, and for the treatment of patients with hypokalemic familial periodic paralysis.

For the prevention of potassium depletion when the dietary intake is inadequate in the following conditions: patients receiving digitalis and diuretics for congestive heart failure, selected patients with hypertension on long-term diuretic therapy, hepatic cirrhosis with ascites, states of aldosterone excess with normal renal function, potassium-losing nephropathy, and with certain diarrheal states.

Precautions

Lactation

Pregnancy

Supplied

Each sustained-release, capsule-shaped, white to off-white mottled tablets imprinted “K-DUR 20” on one side and scored on the other, contains: potassium chloride USP 20 mmol (mEq) (1500 mg). Nomedicinal ingredients: crospovidone, ethylcellulose, hydroxypropylcellulose, magensium stearate, and microcrystalline cellulose. Bottles of 100. Keep tightly closed. Store at controlled room temperature 15 to 30°C.

Contraindications

Potassium supplements are contraindicated in patients with hyperkalemia since a further increase in potassium concentration in such patients can produce cardiac arrest. Hyperkalemia may complicate any of the following conditions: acute and chronic renal failure, extensive tissue breakdown as in severe burns, adrenal insufficiency, or the administration of a potassium-sparing diuretic (e.g. spironolactone, triamterene), or other drugs causing hyperkalemia such as captopril and enalapril.

Slow release potassium chloride preparations have produced esophageal ulceration in certain cardiac patients with esophageal compression due to enlarged left atrium. The administration of these preparations is contraindicated in such patients as well as in patients with dysphagia.

All solid dosage forms of potassium supplements are contraindicated in any patients in whom there is cause for arrest or delay in tablet passage through the gastrointestinal tract. In these instances, potassium supplementation should be with a liquid preparation.

Warnings

Hyperkalemia: In patients with impaired mechanisms for excreting potassium, the administration of potassium salts can produce hyperkalemia and cardiac arrest. This occurs most commonly in patients given potassium by the i.v. route but may also occur in patients given potassium orally. Potentially fatal hyperkalemia can develop rapidly and be asymptomatic. The use of potassium salts in patients with chronic renal disease, or any other condition which impairs potassium excretion, requires particularly careful monitoring of the serum potassium concentration and appropriate dosage adjustment. Hyperkalemia has the potential to promote quinidine toxicity.

Hypokalemia: Hypokalemia should not be treated by the concomitant administration of potassium salts and a potassium-sparing diuretic (e.g. spironolactone, triamterene) or other drugs causing hyperkalemia such as captopril or enalapril since the simultaneous administration of these agents can produce severe hyperkalemia. Hypokalemia in patients with metabolic acidosis should be treated with an alkalinizing potassium salt such as potassium acetate, potassium bicarbonate or potassium citrate.

Gastrointestinal Lesions: Potassium chloride tablets have produced stenotic and/or ulcerative lesions of the small bowel and deaths, in addition to upper gastrointestinal bleeding. These lesions are caused by a high localized concentration of potassium ions in the region of a rapidly dissolving tablet, which injures the bowel wall and thereby produces obstruction, hemorrhage or perforation.

The frequency of gastrointestinal lesions with K-DUR tablet is, at present, unknown. K-DUR tablet should be discontinued immediately and the possibility of bowel obstruction or perforation considered if severe vomiting, abdominal pain, distention, or gastrointestinal bleeding occurs. All oral potassium preparations should be prescribed with particular caution in patients with a history of peptic ulcer.

Adverse Effects

The most common adverse reactions to oral potassium salts are nausea, vomiting, abdominal discomfort and diarrhea. These symptoms are due to irritation of the gastrointestinal tract and are best avoided by increasing fluid intake when possible, taking the dose with meals or reducing the dose. Intestinal bleeding, ulceration, perforation and obstruction have been reported in patients treated with solid dosage forms of potassium salts and may occur with K-DUR (see Contraindications and Warnings).

One of the most severe adverse effects is hyperkalemia (see Contraindications, Warnings and Overdose). Skin rash has been reported rarely with potassium preparations.

Overdose

Symptoms

Treatment

Dosage

The usual dietary intake of potassium by the average adult is 40 to 80 mmol (mEq) (3000 to 6000 mg)/day.

Potassium depletion sufficient to cause hypokalemia usually requires the loss of 200 or more mmol (mEq) (15 000 mg) of potassium from the total body store.

Dosage must be adjusted to the individual needs of each patient but is typically in the range of 20 mmol (mEq) (1500 mg)/day for the prevention of hypokalemia to 40-100 mmol (mEq) (3000-7500 mg)/day or more for the treatment of potassium depletion (see Table 1).

If more than one (1) K-DUR 20 mmol (mEq) (1500 mg) tablet is prescribed/day, the total daily dosage should be divided into 2 or more separate doses.

Tablets should be taken with a glass of water or other liquid.

Patients having difficulty swallowing whole tablets may try one of the following alternate methods of administration. Break the tablet in half, and take each half separately with a glass of water; or prepare an aqueous suspension as follows: Place the whole tablet in approximately one-half glass of water (115 mL). Allow 2 to 3 minutes for the tablet to disintegrate. Stir for about half a minute after the tablet has disintegrated. Drink the entire contents of the glass immediately. Add another small quantity of water, stir and drink immediately. Aqueous suspensions of K-DUR tablets that are not taken immediately should be discarded. The use of other liquids for suspending the tablets is not recommended.