Mechanism of effect
Sodium bicarbonate is a systemic alkalizer, which increases plasma bicarbonate, buffers excess hydrogen ion concentration, and raises blood pH, thereby reversing the clinical manifestations of acidosis.
It is also a urinary alkalizer, increasing the excretion of free bicarbonate ions in the urine, thus effectively raising the urinary pH. By maintaining an alkaline urine, the actual dissolution of uric acid stones may be accomplished.
Sodium bicarbonate acts as an antacid and reacts chemically to neutralize or buffer existing quantities of stomach acid but has no direct effect on its output. This action results in increased pH value of stomach contents, thus providing relief of hyperacidity symptoms.
Pharmacodynamic
Intravenous sodium bicarbonate therapy increases plasma bicarbonate, buffers excess hydrogen ion concentration, raises blood pH and reverses the clinical manifestations of acidosis.
Pharmacokinetics
Onset: 15 min (IV)
Duration: 1-2 hr (IV); 8-10 min (PO)
Therapeutic range: 24-31 mEq/L
Excretion: Urine
Absorption: Well absorbed orally
Drug indications
metabolic acidosisDosage
Usual Adult Dose for Metabolic Acidosis
Parenteral:
If acid-base status is available, dosages should be calculated as follows: 0.2 x weight (kg) x base deficit.
Alternatively:
HCO3 (mEq) required = 0.5 x weight (kg) x [24 - serum HCO3 (mEq/L)].
or
Moderate metabolic acidosis: 50 to 150 mEq sodium bicarbonate diluted in 1 L of D5W to be intravenously infused at a rate of 1 to 1.5 L/hour during the first hour.
Severe metabolic acidosis: 90 to 180 mEq sodium bicarbonate diluted in 1 L of D5W to be intravenously infused at a rate of 1 to 1.5 L/hour during the first hour.
If acid-base status is not available, dosages should be calculated as follows: 2 to 5 mEq/kg IV infusion over 4 to 8 hours; subsequent doses should be based on patient's acid-base status.
Oral:
Moderate metabolic acidosis: 325 to 2000 mg orally 1 to 4 times a day. One gram provides 11.9 mEq (mmoL) each of sodium and bicarbonate.
Usual Adult Dose for Diabetic Ketoacidosis
the initial dosage is 50 mEq sodium bicarbonate in 1 L of appropriate IV solution to be given once.
Usual Adult Dose for Urinary Alkalinization
Parenteral:
50 to 150 mEq sodium bicarbonate diluted in 1 L of D5W to be intravenously infused at a rate of 1 to 1.5 L/hour.
Oral:
325 to 2000 mg orally 1 to 4 times a day. One gram provides 11.9 mEq (mmoL) each of sodium and bicarbonate.
Usual Adult Dose for Dyspepsia
325 to 2000 mg orally 1 to 4 times a day.
Usual Adult Dose for Hyperkalemia
One ampule of 7.5% sodium bicarbonate (44.6 mEq HCO3 ion) may be administered slowly IV over 5 minutes and repeated at 10 to 15 minute intervals if ECG changes persist. The onset of action occurs within 30 minutes and the effect lasts for 1 to 2 hours. The resultant effect restores intracellular potassium levels to normal without decreasing total body potassium stores.
Usual Adult Dose for Asystole
1 mEq/kg slow IV initially, may repeat with 0.5 mEq/kg 10 minutes later one time, or as indicated by the patient's acid-base status.
Usual Pediatric Dose for Metabolic Acidosis
If acid-base status is available, dosages should be calculated as follows:
Infants and Children: HCO3 (mEq) required = 0.3 x weight (kg) x base deficit (mEq/L) OR HCO3 (mEq) required = 0.5 x weight (kg) x [24 - serum HCO3 (mEq/L)].
If acid-base status is not available, dosages should be calculated as follows:
Older children: 2 to 5 mEq/kg IV infusion over 4 to 8 hours; subsequent doses should be based on patient acid-base status.
Usual Pediatric Dose for Urinary Alkalinization
0 to 12 years: 1 to 10 mEq (84 to 840 mg)/kg/day orally in divided doses; dose should be titrated to desired urinary pH.
Greater than 12 to 18 years: 325 to 2000 mg orally 1 to 4 times a day. One gram provides 11.9 mEq (mmol) each of sodium and bicarbonate.
Usual Pediatric Dose for Hyperuricemia Secondary to Chemotherapy
0 to 12 years:
Parenteral:
120 to 200 mEq/m2/day diluted in maintenance IV fluids of 3000 mL/m2/day; titrate to maintain urine pH between 6 and 7.
Oral:
12 g/m2/day divided into 4 doses; titrate to maintain urine pH between 6 and 7.
Usual Pediatric Dose for Asystole
1 mEq/kg slow IV initially, may repeat with 0.5 mEq/kg 10 minutes later one time, or as indicated by the patient acid-base status.
Drug contraindications
Hypersensitivity , Undiagnosed abdominal pain , Hypercarbic acidosis , diuretic-induced hypochloremic alkalosisInteractions
Ethambutol , Acetazolamide , Budesonide , Penicillamine , Dicyclomine , Risedronate , Ofloxacin , Itraconazole , Tetracycline , Gemifloxacin , Dapsone , Doxycycline , Atazanavir , Indinavir , Fleroxacin , Oxytetracycline , Delavirdine , Nitrendipine , Digoxin , Levofloxacin , Minocycline , Moxifloxacin , Nimodipine , Ketoconazole , Iron , Demeclocycline , Dolutegravir , Eltrombopag , Nisoldipine , tiludronate , atovaquone/proguanil , BacampicillinAlerts
Not first-line for resuscitation
Edematous or Na-retaining states, history of CHF, renal impairment, cirrhosis, HTN, children with DKA, concurrent corticosteroid use
May cause hypokalemia
Use caution in patients with cirrhosis, heart failure, renal impairment, peptic ulcer disease, or edema
Avoid extravasation (may cause chemical cellulitis, tissue necrosis, ulceration & sloughing due to alkalinity)
Points of recommendation
Use exactly as directed on the label, or as prescribed by your doctor. Do not use in larger or smaller amounts or for longer than recommended.
Sodium bicarbonate tablets are usually dissolved completely in water before swallowing. Follow all directions on the product label.
Call your doctor if your symptoms do not improve, or if they get worse while using sodium bicarbonate.
Store at room temperature away from moisture and heat.
Avoid taking sodium bicarbonate without a doctor's advice if you regularly take other medicines.
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