potassium salts

potassium salts

(po tass' ee um)

potassium acetate

potassium chloride

Oral:

Apo-K (CAN), Cena-K, Effer-K, Gen-K, Kaon-Cl, Kay Ciel, Kaylixir, K-Dur 10, K-Dur 20, K-Lor, K-Tab, Klor-Con, Klorvess, Klotrix, K-Lyte/Cl, Kolyum, K+ Care ET, K + 8, K + 10, Micro-K Extentabs, Potasalan, Rum-K, Ten K

Injection:

Potassium Chloride

potassium gluconate

Kaon, K-G Elixir, Kolyum, Tri-K, Twin-K

Pregnancy Category C

Drug class

Electrolyte

Therapeutic actions

Principal intracellular cation of most body tissues, participates in a number of physiologic processes—maintaining intracellular tonicity, transmission of nerve impulses, contraction of cardiac, skeletal, and smooth muscle, maintenance of normal renal function; also plays a role in carbohydrate metabolism and various enzymatic reactions.

Indications

·        Prevention and correction of potassium deficiency; when associated with alkalosis, use potassium chloride; when associated with acidosis, use potassium acetate, bicarbonate, citrate, or gluconate

·        IV: Treatment of cardiac arrhythmias due to cardiac glycosides

Contraindications and cautions

·        Contraindicated with allergy to tartrazine, aspirin (tartrazine is found in some preparations marketed as Kaon-Cl, Klor-Con); severe renal impairment witholiguria, anuria, azotemia; untreated Addison's disease; hyperkalemia; adynamia episodica hereditaria; acute dehydration; heat cramps; GI disorders that delay passage in the GI tract.

·        Use cautiously with cardiac disorders, especially if treated with digitalis, pregnancy, lactation.

Available forms

Liquids—20, 40, 45 mEq/15 mL; powders—15, 20, 25 mEq/packet; effervescent tablets—20, 25, 50 mEq; CR tablets—6.7, 8, 10, 20 mEq; CR capsules—8, 10  mEq; tablets—500, 595 mg; injection—2, 4, 10, 20, 30, 40, 60, 90 mEq

Dosages

Individualize dosage based on patient response using serial ECG and electrolyte determinations in severe cases.

ADULTS

Oral

·        Prevention of hypokalemia: 16–24 mEq/day PO.

·        Treatment of potassium depletion: 40–100 mEq/day PO.

IV

WARNING: Do not administer undiluted. Dilute in dextrose solution to 40–80 mEq/L. Use the following as a guide to administration:

Serum K+	Maximum Infusion Rate	Maximum Concentration	Maximum 24-hr Dose
> 2.6 mEq/L	10 mEq/hr	40 mEq/L	200 mEq
< 2 mEq/L	40 mEq/hr	80 mEq/L	400 mEq

PEDIATRIC PATIENTS

·        Replacement: 3 mEq/kg/day or 40 mg/m²/day PO or IV.

GERIATRIC PATIENTS OR PATIENTS WITH RENAL IMPAIRMENT

Carefully monitor serum potassium concentration and reduce dosage appropriately.

Pharmacokinetics

Route	Onset	Peak
Oral	Slow	1–2 hr
IV	Rapid	End of infusion

Metabolism: Cellular; T_1/2: Unknown

Distribution: Crosses placenta; enters breast milk

Excretion: Urine

IV facts

Preparation: Do not administer undiluted potassium IV; dilute in dextrose solution to 40–80 mEq/L; in critical states, potassium chloride can be administered in saline.

Infusion: Adjust dosage based on patient response at a maximum of 10 mEq/L.

Incompatibilities: Do not mix with amphotericin B.

Y-site incompatibilities: Do not give with diazepam, ergotamine, phenytoin.

Adverse effects

·        Dermatologic: Rash

·        GI: Nausea, vomiting, diarrhea, abdominal discomfort, GI obstruction, GI bleeding, GI ulceration or perforation

·        Hematologic: Hyperkalemia—increased serum K⁺, ECG changes (peaking of T waves, loss of P waves, depression of ST segment, prolongation of QTcinterval)

·        Local: Tissue sloughing, local necrosis, local phlebitis, and venospasm with injection

Interactions

Drug-drug

·        Increased risk of hyperkalemia with potassium-sparing diuretics, salt substitutes using potassium

Nursing considerations

Assessment

·        History: Allergy to tartrazine, aspirin; severe renal impairment; untreated Addison's disease; hyperkalemia; adynamia episodica hereditaria; acute dehydration; heat cramps, GI disorders that cause delay in passage in the GI tract, cardiac disorders, lactation

·        Physical: Skin color, lesions, turgor; injection sites; P, baseline ECG; bowel sounds, abdominal examination; urinary output; serum electrolytes, serum bicarbonate

Interventions

·        Arrange for serial serum potassium levels before and during therapy.

·        Administer liquid form to any patient with delayed GI emptying.

·        Administer oral drug after meals or with food and a full glass of water to decrease GI upset.

·        Caution patient not to chew or crush tablets; have patient swallow tablet whole.

·        Mix or dissolve oral liquids, soluble powders, and effervescent tablets completely in 3–8 oz of cold water, juice, or other suitable beverage, and have patient drink it slowly.

·        Arrange for further dilution or dose reduction if GI effects are severe.

·        Agitate prepared IV solution to prevent "layering" of potassium; do not add potassium to an IV bottle in the hanging position.

·        Monitor IV injection sites regularly for necrosis, tissue sloughing, phlebitis.

·        Monitor cardiac rhythm carefully during IV administration.

·        Caution patient that expended wax matrix capsules will be found in the stool.

·        Caution patient not to use salt substitutes.

Teaching points

·        Take drug after meals or with food and a full glass of water to decrease GI upset. Do not chew or crush tablets, swallow tablets whole. Mix or dissolve oral liquids, soluble powders, and effervescent tablets completely in 3–8 ounces of cold water, juice, or other suitable beverage, and drink it slowly. Take the drug as prescribed; do not take more than prescribed.

·        Do not use salt substitutes.

·        You may find wax matrix capsules in the stool. The wax matrix is not absorbed in the GI tract.

·        Have periodic blood tests and medical evaluation.

·        You may experience these side effects: Nausea, vomiting, diarrhea (taking the drugs with meals, diluting them further may help).

·        Report tingling of the hands or feet, unusual tiredness or weakness, feeling of heaviness in the legs, severe nausea, vomiting, abdominal pain, black or tarry stools, pain at IV injection site.

Adverse effects in Italic are most common; those in Bold are life-threatening.