Potassium citrate

Description

Potassium citrate is a citrate salt of potassium with the molecular formula K₃C₆H₅O₇ • H₂O. It is characterized by its transparent crystals or white, granular powder appearance. Potassium citrate is freely soluble in water and slightly soluble in alcohol. The extended-release tablets, USP, are formulated for oral administration and are available in three strengths: 5 mEq (540 mg), 10 mEq (1,080 mg), and 15 mEq (1,620 mg) of potassium citrate, USP as monohydrate. Each tablet also contains inactive ingredients, including carnauba wax and magnesium stearate. Potassium citrate meets the USP Dissolution Test 2 criteria.

Uses and Indications

Potassium citrate extended-release tablet is indicated for the management of renal tubular acidosis (RTA) associated with calcium stones, hypocitraturic calcium oxalate nephrolithiasis of any etiology, and uric acid lithiasis, with or without calcium stones.

There are no teratogenic or nonteratogenic effects associated with this medication.

Dosage and Administration

For patients with severe hypocitraturia (urinary citrate < 150 mg/day), therapy should be initiated at a dosage of 60 mEq per day. This can be administered as 30 mEq two times per day or 20 mEq three times per day. Doses should be taken with meals, within 30 minutes after meals, or at bedtime snack to enhance absorption.

In cases of mild to moderate hypocitraturia (urinary citrate > 150 mg/day), therapy should commence at a dosage of 30 mEq per day. This can be given as 15 mEq two times per day or 10 mEq three times per day, also with meals, within 30 minutes after meals, or at bedtime snack.

It is essential to adhere to these dosing schedules to optimize therapeutic outcomes and ensure patient safety.

Contraindications

Use of this product is contraindicated in the following situations:

Patients with hyperkalemia or conditions predisposing to hyperkalemia, including chronic renal failure, uncontrolled diabetes mellitus, acute dehydration, strenuous physical exercise in unconditioned individuals, adrenal insufficiency, and extensive tissue breakdown, due to the risk of exacerbating elevated potassium levels.

Patients with gastrointestinal conditions that may cause arrest or delay in tablet passage, such as delayed gastric emptying, esophageal compression, intestinal obstruction, or stricture, as these conditions may hinder proper absorption.

Patients with peptic ulcer disease, as the product may exacerbate gastrointestinal irritation.

Patients with active urinary tract infections, due to the potential for worsening the infection.

Patients with renal insufficiency, specifically those with a glomerular filtration rate of less than 0.7 ml/kg/min, as this may lead to accumulation of the product and increased risk of adverse effects.

Warnings and Precautions

Patients receiving potassium citrate should be closely monitored for the development of hyperkalemia, particularly in those with compromised renal function or conditions that impair potassium excretion, such as severe myocardial damage or heart failure. The administration of potassium citrate in these populations poses a significant risk of hyperkalemia, which can lead to cardiac arrest. It is crucial to recognize that hyperkalemia may develop rapidly and can be asymptomatic, necessitating vigilant monitoring of serum potassium levels.

In the event of severe gastrointestinal symptoms, including vomiting, abdominal pain, or gastrointestinal bleeding, potassium citrate should be discontinued immediately. These symptoms may indicate serious underlying conditions such as bowel perforation or obstruction, which require prompt investigation and management.

Healthcare professionals are advised to remain alert to these potential complications and to ensure appropriate monitoring and intervention strategies are in place for patients receiving potassium citrate therapy.

Side Effects

Patients may experience a range of adverse reactions associated with potassium citrate administration. Common adverse reactions include minor gastrointestinal complaints such as abdominal discomfort, vomiting, diarrhea, loose bowel movements, or nausea.

Serious adverse reactions have been reported, notably hyperkalemia, which can occur in patients with impaired mechanisms for excreting potassium. This condition can lead to cardiac arrest and may develop rapidly and asymptomatically. The use of potassium citrate is contraindicated in patients with chronic renal failure or other conditions that impair potassium excretion, such as severe myocardial damage or heart failure. Additionally, gastrointestinal lesions may arise; if patients experience severe vomiting, abdominal pain, or gastrointestinal bleeding, potassium citrate should be discontinued immediately, and the possibility of bowel perforation or obstruction should be investigated.

Certain patient populations are at increased risk for adverse reactions. These include patients with hyperkalemia or conditions predisposing them to hyperkalemia, such as chronic renal failure, uncontrolled diabetes mellitus, acute dehydration, strenuous physical exercise in unconditioned individuals, adrenal insufficiency, and extensive tissue breakdown. Furthermore, patients with delayed gastric emptying, esophageal compression, intestinal obstruction, or stricture may experience complications related to delayed tablet passage through the gastrointestinal tract. Other at-risk groups include those with peptic ulcer disease, active urinary tract infections, and renal insufficiency (with a glomerular filtration rate of less than 0.7 ml/kg/min).

In cases of overdosage, the administration of potassium salts to individuals without predisposing conditions for hyperkalemia rarely results in serious hyperkalemia at recommended dosages. It is crucial to recognize that hyperkalemia is often asymptomatic and may only be indicated by increased serum potassium concentrations and characteristic electrocardiographic changes, such as peaking of the T-wave, loss of the P-wave, depression of the S-T segment, and prolongation of the QT interval. Late manifestations of severe hyperkalemia can include muscle paralysis and cardiovascular collapse due to cardiac arrest.

Drug Interactions

Concomitant administration of potassium-sparing diuretics is contraindicated due to the potential for severe hyperkalemia. It is advised to avoid the use of these agents together.

Drugs that slow gastrointestinal transit time, including anticholinergics, may exacerbate gastrointestinal irritation associated with potassium salts. Caution is recommended when these agents are used concurrently.

Patients receiving renin-angiotensin-aldosterone inhibitors should be monitored for signs of hyperkalemia, as the combination may increase the risk of elevated potassium levels.

Nonsteroidal anti-inflammatory drugs (NSAIDs) may also elevate the risk of hyperkalemia when used in conjunction with potassium salts. Monitoring of potassium levels is advised in patients taking these medications together.

Packaging & NDC

The table below lists all NDC Code configurations of Potassium Citrate, the U.S. brand-name prescription product. Columns show Packaging, Formulation Type, and Active Ingredient Strength.

Pediatric Use

Safety and effectiveness in pediatric patients have not been established. Therefore, the use of this medication in children is not recommended until further data is available to support its use in this population.

Geriatric Use

Elderly patients may exhibit reduced kidney function and increased sensitivity to side effects, which could necessitate dosage adjustments or increased monitoring. While specific dosage adjustments for this population are not detailed, caution should be exercised due to potential renal insufficiency and other age-related factors.

It is essential for healthcare providers to monitor elderly patients closely for signs of hyperkalemia and other adverse reactions, particularly in those with underlying health conditions that may affect potassium excretion. Given these considerations, careful assessment and ongoing evaluation of treatment efficacy and safety are recommended for geriatric patients.

Pregnancy

Pregnant patients should be aware that animal reproduction studies have not been conducted with potassium citrate. Therefore, it is not known whether potassium citrate can cause fetal harm when administered to a pregnant woman or if it can affect reproductive capacity. Given the lack of data, potassium citrate should be prescribed to pregnant women only if clearly needed, weighing the potential benefits against any unknown risks. Healthcare professionals are advised to exercise caution and consider alternative treatments when appropriate.

Lactation

Potassium citrate is excreted in human milk, but it is not known if it affects the normal potassium ion content, which is approximately 13 mEq/L. Due to the lack of data on its impact on breastfed infants, potassium citrate should be administered to lactating mothers only if clearly needed.

Renal Impairment

Patients with impaired mechanisms for excreting potassium are at an increased risk of hyperkalemia when administered potassium citrate. This condition can lead to cardiac arrest and may develop rapidly, often without symptoms. Therefore, the use of potassium citrate is contraindicated in patients with chronic renal failure or any other conditions that significantly impair potassium excretion, such as severe myocardial damage or heart failure. Careful consideration and monitoring are essential in this patient population to prevent potentially fatal outcomes.

Hepatic Impairment

Patients with hepatic impairment have not been specifically studied in relation to the use of this medication. Consequently, there are no established dosage adjustments, special monitoring requirements, or precautions outlined for individuals with compromised liver function. It is recommended that healthcare providers exercise caution when prescribing this medication to patients with hepatic impairment, given the lack of data on its safety and efficacy in this population. Regular monitoring of liver function may be prudent in these cases, although specific parameters are not defined in the available information.

Overdosage

The administration of potassium salts in individuals without predisposing conditions for hyperkalemia typically does not lead to serious hyperkalemia when dosages are within recommended limits. However, it is crucial to recognize that hyperkalemia is often asymptomatic and may only be indicated by elevated serum potassium levels and specific electrocardiographic changes. These changes can include peaking of the T-wave, loss of the P-wave, depression of the S-T segment, and prolongation of the QT interval. In advanced cases, late manifestations may present as muscle paralysis and cardiovascular collapse due to cardiac arrest.

Management of Hyperkalemia

In the event of hyperkalemia, several treatment measures should be implemented:

• Monitoring: Patients should be closely monitored for arrhythmias and electrolyte imbalances.

• Medication Review: It is essential to discontinue any medications that contain potassium or possess potassium-sparing properties. This includes potassium-sparing diuretics, angiotensin receptor blockers (ARBs), angiotensin-converting enzyme (ACE) inhibitors, nonsteroidal anti-inflammatory drugs (NSAIDs), and certain nutritional supplements.

• Dietary Restrictions: Patients should avoid foods high in potassium, such as almonds, apricots, bananas, various beans (lima, pinto, white), cantaloupe, canned carrot juice, figs, grapefruit juice, halibut, milk, oat bran, potatoes (with skin), salmon, spinach, tuna, and others.

• Calcium Administration: Intravenous calcium gluconate may be administered if the patient is at low or no risk of developing digitalis toxicity.

• Insulin and Dextrose: An intravenous infusion of 10% dextrose solution containing 10 to 20 units of crystalline insulin per 1,000 mL should be given at a rate of 300 to 500 mL/hr.

• Correction of Acidosis: If acidosis is present, it should be corrected with intravenous sodium bicarbonate.

• Dialysis: Hemodialysis or peritoneal dialysis may be necessary in severe cases.

• Use of Exchange Resins: While exchange resins can be utilized, they should not be relied upon as the sole treatment for acute hyperkalemia.

It is important to note that lowering potassium levels too rapidly in patients who are taking digitalis can lead to digitalis toxicity, necessitating careful management of potassium levels during treatment.

Nonclinical Toxicology

Animal reproduction studies have not been conducted to evaluate the teratogenic effects of potassium citrate. Consequently, it remains unknown whether potassium citrate can cause fetal harm when administered to a pregnant woman or if it can affect reproductive capacity. Therefore, potassium citrate should be administered to pregnant women only if clearly needed.

Regarding non-teratogenic effects, the normal potassium ion content of human milk is approximately 13 mEq/L. It is currently unknown if potassium citrate influences this potassium content. As such, potassium citrate should be given to breastfeeding women only if clearly needed.

No specific details are available concerning nonclinical toxicology or animal pharmacology and toxicology.

Postmarketing Experience

Reports of side effects have been received through voluntary submissions and surveillance programs. Patients are encouraged to consult their healthcare provider for medical advice regarding any adverse effects experienced. Additionally, side effects can be reported to the FDA at 1-800-FDA-1088.

Patient Counseling

Patients should be advised to take each dose of the medication without crushing, chewing, or sucking the tablet to ensure proper absorption and effectiveness. It is crucial for patients to take this medicine only as directed, particularly if they are also using diuretics and digitalis preparations, as this can affect the medication's efficacy and safety.

Patients should be instructed to consult their doctor if they experience any difficulty swallowing the tablets or if they feel that the tablet is sticking in their throat. Additionally, they should be made aware of the importance of reporting any signs of gastrointestinal bleeding, such as tarry stools, to their doctor immediately.

Healthcare providers should inform patients that their doctor will conduct regular blood tests and electrocardiograms to monitor their safety while on this medication. Patients should also be encouraged to reach out to their doctor for medical advice regarding any side effects they may experience. Furthermore, they can report side effects to the FDA at 1-800-FDA-1088.

Storage and Handling

The product is supplied in a tight container as defined by the United States Pharmacopeia (USP). It should be stored at a temperature range of 20° to 25°C (68° to 77°F), in accordance with USP Controlled Room Temperature guidelines. Proper adherence to these storage conditions is essential to maintain the integrity and efficacy of the product.

Additional Clinical Information

No further data are available.

FDA Insert (PDF)

This document is the official FDA-approved prescribing information for Potassium Citrate as submitted by Zydus Pharmaceuticals (USA) Inc.. It includes detailed information about indications, dosage, contraindications, warnings, and clinical pharmacology.

View full prescribing information (PDF)