AMMONIUM CHLORIDE

AMMONIUM CHLORIDE
(ah-mo'ni-um)
Classifications: electrolytic balance agent;
Therapeutic: acidfier; electrolyte replacement
Pregnancy Category: B

Availability

26.75% or 5 mEq/mL solution; 500 mg tablets; 486 mg enteric-coated tablets

Action

Acidifying property is due to conversion of ammonium ion (NH₄⁺) to urea in liver with liberation of H⁺ and Cl^–. Potassium excretion also increases acid, but to a lesser extent.

Therapeutic Effect

Effective as a systemic acidifier in metabolic alkalosis by releasing H⁺ ions which lower pH.

Uses

Treatment of hypochloremic states and metabolic alkalosis. Diuretic or urinary acidifying agent.

Contraindications

Severe renal or hepatic insufficiency; primary respiratory acidosis.

Cautious Use

Cardiac edema, cardiac insufficiency, pulmonary insufficiency; pregnancy (category B), lactation.

Route & Dosage

Urine Acidifier, Diuretic
Adult: PO 4–12 g/d divided q4–6h
Child: PO 75 mg/kg/d in 4 divided doses

Metabolic Alkalosis and Hypochloremic States
Adult/Child: IV Dose calculated on basis of CO₂ combining power or serum Cl deficit, 50% of calculated deficit is administered slowly

Administration

Oral

Give after meals for best tolerance or use enteric-coated tablets. Tablets should be swallowed whole.
Store in airtight container.

Intravenous

Check with physician for slower rate for infants.

PREPARE: Intermittent: Dilute each 20 mL vial in 500–1000 mL NS. Do not exceed a concentration of 1–2%.

ADMINISTER: Intermittent: Give slowly to avoid serious adverse effects (ammonia toxicity) and local irritation and pain. Give at a rate not to exceed 5 mL/min.

INCOMPATIBILITIES Solution/additive: Codeine phosphate, dimenhydrinate. Y-site: Warfarin.

Avoid freezing.
Concentrated solutions crystallize at low temperatures.
Crystals can be dissolved by placing intact container in a warm water bath and warming to room temperature.

Adverse Effects (≥1%)

Body as a Whole: Most secondary to ammonia toxicity. CNS: Headache, depression, drowsiness, twitching, excitability; EEG abnormalities. CV: Bradycardia and other arrhythmias. GI: Gastric irritation, nausea, vomiting, anorexia. Metabolic: Metabolic acidosis, hyperammonia. Respiratory: Hyperventilation. Skin: Rash. Urogenital: Glycosuria. Other: Pain and irritation at IV site.

Diagnostic Test Interference

Ammonium chloride may increase blood ammonia and AST, decrease serum magnesium (by increasing urinary magnesium excretion), and decrease urine urobilinogen.

Interactions

Drug: Aminosalicylic acid may cause crystalluria; increases urinary excretion of amphetamines, flecainide, mexiletine, methadone, ephedrine, pseudoephedrine; decreased urinary excretion of sulfonylureas, salicylates.

Pharmacokinetics

Absorption: Completely absorbed in 3–6 h. Metabolism: In liver to HCl and urea. Elimination: Primarily in urine.

Nursing Implications

Assessment & Drug Effects

Assess IV infusion site frequently for signs of irritation. Change site as warranted.
Monitor for S&S of: metabolic acidosis (mental status changes including confusion, disorientation, coma, respiratory changes including increased respiratory rate and depth, exertional dyspnea); ammonium toxicity (cardiac arrhythmias including bradycardia, irregular respirations, twitching, seizures).
Monitor I&O ratio and pattern. The diuretic effect of ammonium chloride is compensatory and lasts only 1–2 d.
Lab tests: Baseline and periodic determinations of CO₂ combining power, serum electrolytes, and urinary and arterial pH during therapy to avoid serious acidosis.

Patient & Family Education

Report pain at IV injection site.

Common adverse effects in italic, life-threatening effects underlined; generic names in bold; classifications in SMALL CAPS; Canadian drug name; Prototype drug

(150)