Dosage Forms
Excipient information presented when available (limited, particularly for generics); consult specific product labeling. [DSC] = Discontinued product
Solution, Oral:
Virtrate-3: Citric acid 334 mg, sodium citrate 500 mg, and potassium citrate 550 mg per 5 mL (473 mL [DSC]) [sugar free; contains fd&c yellow #6 (sunset yellow), polyethylene glycol, propylene glycol, saccharin sodium, sodium benzoate; raspberry flavor]
Generic: Citric acid 334 mg, sodium citrate 500 mg, and potassium citrate 550 mg per 5 mL (473 mL)
Pharmacokinetics/Pharmacodynamics
Metabolism
≥95% via hepatic oxidation to bicarbonate
Excretion
Urine (<5% as unchanged drug)
Use: Labeled Indications
Conditions where long-term maintenance of an alkaline urine is desirable as in control and dissolution of uric acid and cystine calculi of the urinary tract
Contraindications
Severe renal impairment with oliguria or azotemia; untreated Addison’s disease; severe myocardial damage.
Dosage and Administration
Dosing: Adult
Alkalinizing agent/bicarbonate precursor/potassium supplement: Oral: 15-30 mL diluted in water after meals and at bedtime
Dosing: Geriatric
Refer to adult dosing.
Dosing: Pediatric
Note: Consider the contribution of sodium and potassium when determining the appropriate bicarbonate replacement: 1 mL of oral solution contains 2 mEq of bicarbonate, 1 mEq of sodium, and 1 mEq of potassium. Individualize dose as determined by disease and patient-specific targets.
Renal tubular acidosis (RTA), distal (Type 1): Limited data available: Note: Dose requirements may vary with age. Infants, Children, and Adolescents: Oral: Usual dose: 2 to 4 mEq bicarbonate/kg/day (1 to 2 mL/kg/day) in divided doses; reported range: 1 to 7 mEq bicarbonate/kg/day; adjust dose to maintain target serum CO2 (Chan 2001; Kliegman 2016; Rodríguez Soriano 2002; Santos 1986).
Renal tubular acidosis (RTA), proximal (Type 2): Limited data available: Note: Dose requirements may vary with age; for Type 2 RTA, bicarbonate doses are higher than those required for other types of RTA. Infants, Children, and Adolescents: Oral: Usual range: 10 to 20 mEq bicarbonate/kg/day (5 to 10 mL/kg/day) in divided doses (Chan 2001; Kliegman 2016; Rodríguez Soriano 2002); Note: May not be appropriate as monotherapy in some cases due to high therapeutic alkali requirement and corresponding potassium load; could be used in combination with sodium citrate formulations to meet alkali needs (Rodríguez Soriano 2002).
Systemic alkalinization; chronic:
Volume-based dosing: Children and Adolescents: Oral: 5 to 15 mL (10 to 30 mEq bicarbonate) per dose after meals and at bedtime
Weight-based dosing (mEq bicarbonate/kg): Limited data available: Infants, Children, and Adolescents: Oral: 2 to 3 mEq bicarbonate/kg/day (1 to 1.5 mL/kg/day) in 3 to 4 divided doses; adjust dose to targeted serum bicarbonate levels; typical adult doses do not exceed 60 mEq/dose (30 mL/dose) (Kliegman 2007)
Administration
Administer after meals. Dilute with water prior to administration. Chilling solution prior to dosing helps to enhance palatability. May follow dose with additional fluids.
Dietary Considerations
Should be taken after meals to avoid GI upset or laxative effect.
Storage
Store at controlled room temperature of 20°C to 25°C (68°F to 77°F); do not freeze. Protect from excessive heat.
Drug Interactions
Aliskiren: Potassium Salts may enhance the hyperkalemic effect of Aliskiren. Monitor therapy
Alpha-/Beta-Agonists (Indirect-Acting): Alkalinizing Agents may increase the serum concentration of Alpha-/Beta-Agonists (Indirect-Acting). Monitor therapy
Aluminum Hydroxide: Citric Acid Derivatives may increase the absorption of Aluminum Hydroxide. Monitor therapy
Amantadine: Alkalinizing Agents may increase the serum concentration of Amantadine. Monitor therapy
Amphetamines: Alkalinizing Agents may decrease the excretion of Amphetamines. Management: Consider alternatives to using amphetamines and alkalinizing agents in combination. If these agents must be used together, patients should be monitored closely for excessive amphetamine effects. Consider therapy modification
Angiotensin II Receptor Blockers: Potassium Salts may enhance the hyperkalemic effect of Angiotensin II Receptor Blockers. Monitor therapy
Angiotensin-Converting Enzyme Inhibitors: Potassium Salts may enhance the hyperkalemic effect of Angiotensin-Converting Enzyme Inhibitors. Monitor therapy
Anticholinergic Agents: May enhance the ulcerogenic effect of Potassium Citrate. Avoid combination
Drospirenone: Potassium Salts may enhance the hyperkalemic effect of Drospirenone. Monitor therapy
Eplerenone: May enhance the hyperkalemic effect of Potassium Salts. Management: This combination is contraindicated in patients receiving eplerenone for treatment of hypertension. Consider therapy modification
Heparin: May enhance the hyperkalemic effect of Potassium Salts. Monitor therapy
Heparins (Low Molecular Weight): May enhance the hyperkalemic effect of Potassium Salts. Monitor therapy
Mecamylamine: Alkalinizing Agents may increase the serum concentration of Mecamylamine. Monitor therapy
Memantine: Alkalinizing Agents may increase the serum concentration of Memantine. Monitor therapy
Nicorandil: May enhance the hyperkalemic effect of Potassium Salts. Monitor therapy
Potassium-Sparing Diuretics: Potassium Salts may enhance the hyperkalemic effect of Potassium-Sparing Diuretics. Consider therapy modification
QuiNINE: Alkalinizing Agents may increase the serum concentration of QuiNINE. Monitor therapy
Adverse Reactions
Frequency not defined.
Cardiovascular: Cardiac abnormalities
Endocrine & metabolic: Metabolic alkalosis, calcium levels, hyperkalemia, hypernatremia
Gastrointestinal: Diarrhea
Neuromuscular & skeletal: Tetany
Warnings/Precautions
Disease-related concerns:
- Cardiovascular disease: Use with caution in patients with heart failure or hypertension; contains sodium.
- Edema: Use with caution in patients with peripheral or pulmonary edema; contains sodium.
- Hepatic impairment: Citrate is converted to bicarbonate in the liver; this conversion may be blocked in patients in hepatic failure.
- Renal impairment: Use with caution in patients with renal impairment; contains sodium. Contraindicated in patients with severe impairment.
- Severely ill: Use with caution in patients who are severely ill; conversion to bicarbonate may be impaired.
- Shock: Use with caution in patients who are in shock; conversion to bicarbonate may be impaired.
Concurrent drug therapy issues:
- Digitalis: Use with caution in digitalized patients; may be more susceptible to potentially life-threatening cardiac effects with rapid changes in serum potassium concentrations.
- Potassium-altering therapies: Use with caution in patients receiving concomitant medications or therapies that increase potassium (eg, ACEI, potassium-sparing diuretics, potassium containing salt substitutes).
Dosage form specific issues:
- Benzyl alcohol and derivatives: Some dosage forms may contain sodium benzoate/benzoic acid; benzoic acid (benzoate) is a metabolite of benzyl alcohol; large amounts of benzyl alcohol (≥99 mg/kg/day) have been associated with a potentially fatal toxicity (“gasping syndrome”) in neonates; the “gasping syndrome” consists of metabolic acidosis, respiratory distress, gasping respirations, CNS dysfunction (including convulsions, intracranial hemorrhage), hypotension, and cardiovascular collapse (AAP ["Inactive" 1997]; CDC, 1982); some data suggests that benzoate displaces bilirubin from protein binding sites (Ahlfors, 2001); avoid or use dosage forms containing benzyl alcohol derivative with caution in neonates. See manufacturer’s labeling.
- Propylene glycol: Some dosage forms may contain propylene glycol; large amounts are potentially toxic and have been associated hyperosmolality, lactic acidosis, seizures, and respiratory depression; use caution (AAP ["Inactive" 1997]; Zar, 2007).
Monitoring Parameters
Serum potassium, sodium, and bicarbonate; urinary pH
Patient Education
- Discuss specific use of drug and side effects with patient as it relates to treatment. (HCAHPS: During this hospital stay, were you given any medicine that you had not taken before? Before giving you any new medicine, how often did hospital staff tell you what the medicine was for? How often did hospital staff describe possible side effects in a way you could understand?)
- Have patient report immediately to prescriber signs of high potassium (abnormal heartbeat, confusion, dizziness, passing out, weakness, shortness of breath, or numbness or tingling feeling); severe nausea; severe vomiting; abdominal edema; severe abdominal pain; black, tarry, or bloody stools; or vomiting blood (HCAHPS).
- Educate patient about signs of a significant reaction (eg, wheezing; chest tightness; fever; itching; bad cough; blue skin color; seizures; or swelling of face, lips, tongue, or throat). Note: This is not a comprehensive list of all side effects. Patient should consult prescriber for additional questions.
Intended Use and Disclaimer: Should not be printed and given to patients. This information is intended to serve as a concise initial reference for healthcare professionals to use when discussing medications with a patient. You must ultimately rely on your own discretion, experience and judgment in diagnosing, treating and advising patients.
