Pharmacologic class: Mineral, electrolyte
Therapeutic class: Electrolyte replacement, nutritional supplement
Pregnancy risk category C
Maintains acid-base balance, isotonicity, and electrophysiologic balance throughout body tissues; crucial to nerve impulse transmission and contraction of cardiac, skeletal, and smooth muscle. Also essential for normal renal function and carbohydrate metabolism.
Concentrate for injection: 2 mEq/ml in 20-, 50-, and 100-ml vials; 4 mEq/ml in 50-ml vials
➣ To prevent or treat potassium depletion; diabetic acidosis; metabolic alkalosis; arrhythmias; periodic paralysis attacks; hyperadrenocorticism; primary aldosteronism; healing phase of burns or scalds; overmedication with adrenocorticoids, testosterone, or corticotropin
Adults: Dosage highly individualized. For potassium level above 2.5 mEq/L, give 40 mEq/L as additive to I.V. infusion at a maximum rate of 10 mEq/hour; maximum daily dosage is 200 mEq. For potassium level less than 2 mEq/L, give 80 mEq/L as additive to I.V. infusion at a maximum rate of 40 mEq/hour (with cardiac monitoring); maximum daily dosage is 400 mEq.
Children: Dosage highly individualized; up to 3 mEq/kg or 40 mEq/m2/day as additive to I.V. infusion.
• Acute dehydration
• Heat cramps
• Hyperkalemia
• Hyperkalemic familial periodic paralysis
• Severe renal impairment
• Severe hemolytic reactions
• Untreated Addison's disease
• Severe tissue trauma
• Concurrent use of potassium-sparing diuretics, angiotensin-converting enzyme (ACE) inhibitors, or salt substitutes containing potassium
Use cautiously in:
• cardiac disease, renal impairment, diabetes mellitus, hypomagnesemia
• pregnant or breastfeeding patients
• children (safety and efficacy not established).
• Make sure patient is well hydrated and urinating before starting therapy.
☞ Give only as additive to I.V. infusion. Never give by I.V. push or I.M. route, and never give undiluted. Use peripheral line with maximum rate of 40 mEq/hour (with cardiac monitoring).
☞ To ensure that potassium is well mixed in compatible solution, don't add potassium to I.V. bottle in hanging position.
☞ Dilute in compatible I.V. solution. Administer slowly to reduce risk of fatal hyperkalemia.
• Know that maximum infusion rate without cardiac monitoring is 20 mEq/hour. Infusion rates above 20 mEq/hour necessitate cardiac monitoring.
• If patient complains of burning with I.V. administration, decrease flow rate.
• Be aware that potassium preparations are not interchangeable.
• Know that dosages are expressed in mEq of potassium and that potassium acetate contains 10.2 mEq/g.
CNS: confusion, unusual fatigue, restlessness, asthenia, flaccid paralysis, paresthesia, absent reflexes
CV: ECG changes, hypotension, arrhythmias, heart block, cardiac arrest
GI: nausea, vomiting, diarrhea, abdominal discomfort, flatulence
Metabolic: hyperkalemia
Musculoskeletal: weakness and heaviness of legs
Respiratory: respiratory paralysis Other: irritation at I.V. site
Drug-drug. ACE inhibitors, potassium-sparing diuretics, other potassium-containing preparations: increased risk of hyperkalemia
Drug-diagnostic tests. Potassium: increased level
Drug-food. Salt substitutes containing potassium: increased risk of hyperkalemia
Drug-herbs. Dandelion: increased risk of hyperkalemia
Licorice: decreased response to potassium
• Monitor renal function, fluid intake and output, and potassium, creatinine, and blood urea nitrogen levels.
☞ Know that potassium is contra-indicated in severe renal impairment and must be used with extreme caution (if at all) in patients with any degree of renal impairment, because of risk of life-threatening hyperkalemia.
• Assess vital signs and ECG. Watch for arrhythmias.
• Evaluate patient's neurologic status. Stay alert for neurologic complications.
• Monitor I.V. site for irritation.
• Instruct patient to report unusual pain, redness, swelling, or other reactions at infusion site.
• Advise patient to report nausea, vomiting, confusion, numbness and tingling, unusual tiredness or weakness, or heavy feeling in legs.
• Instruct patient to avoid salt substitutes.
• As appropriate, review all other significant and life-threatening adverse reactions and interactions, especially those related to the drugs, tests, foods, and herbs mentioned above.