sodium bicarbonate
Bell/ans, Neut, Soda Mint

Available forms
Available by prescription only
Injection: 4% (2.4 mEq/5 ml), 4.2% (5 mEq/10 ml), 5% (297.5 mEq/500 ml), 7.5% (8.92 mEq/10 ml and 44.6 mEq/50 ml), 8.4% (10 mEq/10 ml and 50 mEq/50 ml)
Available without a prescription
Tablets: 325 mg, 500 mg, 520 mg, 650 mg

Indications and dosages
 Adjunct to advanced cardiovascular life support during CPR. Adults: Although no longer routinely recommended, inject either 300 to 500 ml of a 5% solution or 200 to 300 mEq of a 7.5% or 8.4% solution as rapidly as possible. Base further doses on subsequent blood gas values. Alternatively, 1 mEq/kg dose; then repeat 0.5 mEq/kg every 10 minutes.
Children age 2 and younger: 1 mEq/kg I.V. bolus or intraosseous injection of a 4.2% to 8.4% solution. Dose may be repeated q 10 minutes depending on blood gas values. Don’t exceed daily dose of 8 mEq/kg.
 Severe metabolic acidosis. Adults: Dose depends on blood carbon dioxide content, pH, and patient’s clinical condition. Generally, administer 90 to 180 mEq/L I.V. during first hour; then adjust, p.r.n.
 Less-urgent metabolic acidosis. Adults and adolescents: 2 to 5 mEq/kg as a 4- to 8-hour I.V. infusion.
 Urine alkalization. Adults: 48 mEq (4 g) P.O. initially; then 12 to 24 mEq (1 to 2 g) q 4 hours. May need doses of 30 to 48 mEq (2.5 to 4 g) q 4 hours, up to 192 mEq (16 g) daily.
Children: 1 to 10 mEq (84 to 840 mg)/kg daily.
 Antacid. Adults: 300 mg to 2 g P.O. one to four times daily.

Pharmacodynamics
Alkalizing buffering action: Sodium bicarbonate is an alkalinizing agent that dissociates to provide bicarbonate ion. Bicarbonate in excess of that needed to buffer hydrogen ions causes systemic alkalinization and, when excreted, urine alkalinization as well.
Oral antacid action: Taken orally, sodium bicarbonate neutralizes stomach acid by the above mechanism.

Pharmacokinetics
Absorption: Well absorbed after oral administration as sodium ion and bicarbonate.
Distribution: Occurs naturally and is confined to the systemic circulation.
Metabolism: None.
Excretion: Filtered and reabsorbed by the kidney; less than 1% of filtered bicarbonate is excreted.

Contraindications and precautions
Contraindicated in patients with metabolic or respiratory alkalosis; in those who are losing chlorides by vomiting or from continuous GI suction; in those receiving diuretics known to produce hypochloremic alkalosis; and in patients with hypocalcemia in which alkalosis may produce tetany, hypertension, seizures, or heart failure. Orally administered sodium bicarbonate is contraindicated in patients with acute ingestion of strong mineral acids.
  Use extreme caution when giving drug to patients with heart failure, renal insufficiency, or other edematous or sodium-retaining conditions.

Interactions
Drug-drug. Amphetamines, ephedrine, flecainide, mecamylamine, pseudoephedrine, quinidine: If urine alkalinization occurs, sodium bicarbonate increases half-life of these drugs. Monitor patient closely.
Chlorpropamide, lithium, methotrexate, salicylates, tetracyclines: Increases urinary excretion of these drugs. Monitor patient closely.
Corticosteroids: May increase sodium retention. Monitor patient closely.

Adverse reactions
GI: gastric distention, belching, flatulence.
Metabolic: metabolic alkalosis, hypernatremia, increased serum lactate levels, hyperosmolarity (with overdose).
Skin: local pain and irritation at injection site.

Effects on lab test results
• May increase sodium and lactate levels. May decrease potassium levels.

Overdose and treatment
Overdose may cause depressed consciousness and obtundation from hypernatremia, tetany from hypocalcemia, arrhythmias from hypokalemia, and seizures from alkalosis.
 Correct fluid, electrolyte, and pH abnormalities. Monitor vital signs and fluid and electrolytes closely.

Special considerations
 ALERT Sodium bicarbonate isn’t routinely recommended for use in cardiac arrest because it may produce a paradoxical acidosis from carbon dioxide production.
• With I.V. infusion, watch for irritation and infiltration; extravasation can cause tissue damage and necrosis. Addition of calcium salts may cause precipitate; bicarbonate may inactivate catecholamines in solution (epinephrine, phenylephrine, and dopamine).
• Discourage use as an oral antacid because of hazardous excessive systemic absorption.
• Drug may be used as an adjunct to treat hyperkalemia (with dextrose and insulin).
• Monitor blood pH, partial pressure of arterial oxygen, partial pressure of arterial carbon dioxide, and serum electrolytes.
• Assess patient for milk-alkali syndrome if drug use is long-term.
• Monitor vital signs regularly; when drug is used as urine alkalinizer, monitor urine pH.
Pregnant patients
• Safety hasn’t been established for use during pregnancy.
Breast-feeding patients
• It isn’t known if sodium bicarbonate appears in breast milk. Use cautiously in breast-feeding women.
Pediatric patients
• Avoid rapid infusion (10 ml/minute) of hypertonic solutions in children younger than age 2.
Geriatric patients
• Elderly patients with heart failure or other fluid-retaining conditions are at greater risk for increased fluid retention; use drug cautiously.

Patient education
• Advise patient not to take drug with milk. Doing so may cause hypercalcemia, alkalosis, and possibly renal calculi.
• If patient takes an oral dose form, tell patient to take drug 1 hour before or 2 hours after taking enteric-coated drugs because sodium bicarbonate may cause enteric-coated products to dissolve in the stomach.

Reactions may be common, uncommon, life-threatening, or COMMON AND LIFE THREATENING.
◆ Canada only
◇ Unlabeled clinical use