Drug Interaction:
Interacting drugs- summary
+ Potassium salts
ACE inhibitors
concurrent use result in elevated serum potsssium
concentrations in certain patients
Potassium sparing diuretics/ pot contg salt substitutes
potassium sparing diuretics and potassium containing
salt substitutes will increase potassium retention and can
produce severe hyperkalemia
Potassium salts +
Digitalis
in patients on digoxin, hypokalemai may result in digoxin
toxicity. Use caution if discontinuing a potassium preparation
in patients maintained on digoxin.
Adverse Reaction:
Hyperkalaemia with serious disturbances in cardiac rhythum and arrest (seen with I.V.use).
Hyperkalaemia, GI discomfort and irritation,diarrhoea and muscle weakness, chest pain,
paralysis.
Wax matrix preparation:Reports of oesophagael structure/ haemorrhage. Ulceration, bleeding and perforation of small intestine.
IV administration: Phlebitis and pain at site of injection.
Hyperkalemia- signs and symptoms- paresthesias of extremities, flaccid paralysis, muscle or respiratory paralysis, weakness, listlessness, mental confusion, weakness and heaviness of the legs hypotension, cardiac
arrhythmias, heart block, ECG abnormalities, such as disappearnce of P waves,
GI- nausea, vomiting, abdominal pain, diarrhea,
Reactions due to solution or technique of administration- febrile response, infectionat injection site, venous thrombosis, phlebitis extending from injection site, extravasation, hypervolemia, hyperkalemia, venospasm.
Contra-Indications:
Hyperkalaemia, renal imapirment, diabetic ketoacidosis, acute hydration, adrenal insufficiency,
extensive tissue breakdown as in severe burns.
Special precautions:
In patients with GI ulceration/perforation oral adminstratin avoided. Pregnancy, frequent checks of the clinical status of patient and periodic ECG and/or serum potassium levels should be made. Caution in presence of cardiac disease.
Monitoring- close medical supervision with frequent ECGs and serum potassoium detreminations. Plasma levels are not necessary indicative of tissue levels.
Special risk patients- use with caution in the presence of cardiac disease, particularly in digitaized patients or in the presence of renal disease, metabolic acidosis. Additions disease, acute dehydration, prolonged or severe diarrhea, familial periodic paralysis, hypoaldrenalism, hyperkalemia, hyponatremia, and myotoma congenita.
Fluid/solute overload- IV admin can cause fluid or solute overloading resulting in dilution of serum electrolyte concentrations, overhydration, congested states or pulmonary edema.
Warnings-
Potassium intoxification- do not infuse rapidly.High plasma concentrations of potassium may cause death through cardiac depression, arrhythmias or arrest. Monitor potassiumreplacement therapy whenever possible by continous or serial ECG.
Renal impairment or adrenal insufficiency- may cause potassium intoxification. Potassium salts can produce hyperkalemia and cardiac arrest. Potentialy fatal hyperkalemia can develop rapidly and be asymptomatic. Use with great caution.
Concentratrated potassium solutions- are for IV admixtures only.,do not use undiluted.. Direct injection may be instantaneously fatal.
Metabolic acidosis- treat associated hypokalemia with an alkalinizing potassium salt eg bicarbonate citrate, gluconate, acetate.
Musculoskeletal/cardiac effects- when sodium or potassium concentration is reduced moderate elevation of serum potassium maycause toxic effects on the heart and skeletal muscle.
Renal function impairment-discontinue potassium-continuing solutions if signs of renal insufficiency develop during infusions.
Pregnancy- give to a pregnant woman only if clearly indicated.
Lactation- excercise caution when administering to a nursing woman.
Dosages/ Overdosage Etc:
Dosage-
Potassium acetate 10.2 mEq/g
Potassium chloride 13.4 mEq/g
Dibasaci potassium phosphate 11.5 mE/g
Monobasic potassium phosphate 7.3 mE/g
Do not administer undiluted potassium
Too rapid infusionof hypertonic soutions may cause local pain and rarely vein irritation. Adjust rate according to
tolerance
Overdosage-
If excretory mechnisms are impaired or if potassium isadministered too rapidly IV, potentially fatal hyperkalemia
can result.
Symptoms
Increased serum potassium concentration
Characterized ECG changes
Muscular weakness progressing to quadriplagia
Respiratory paralysis
Treatment
1. Terminate Potassium administration
2. Monitor ECG
3. Infuse combined dextrose in ratio of 3g dextrose to 1 unit regular insulin
4. Administer sodium bicarbonate 50 to 100mEq IV to reverse acidosis and to produce intracellular shift
5. Give 10 to 100ml calcium gliconate or calcium chloride 10% to reverse ECG changes
6. To remove potassium from the body use sodium polystrene rersin or hemodialysis or pertional dialysis
Missed dose-
1. If you miss a dose of this medicine and remember within 2 hours take the missed dose right away with food or liquids.
2. Then go back to your regular dosing schedule.
3. However, if do not remember until later skip the missed dose and then go back to your regular dosing schedule
4. Do not double doses
Patient Information:
1. May cause GI upset, take after meals or with food and full glass of water.
2. Do not chew or crush tablets, swallow whole
3. Oral liquids, soluble powders and effervescent tablets- Mix or dissolve completely in 3 to 8 ounces of cold water, juice or other suitable beverage and drink slowly
4. Following release of potassium chloride, the expanded wax matrix which is not absorbable can be found in the stool. This is no cause for concern
5. Do not use salt substitutes concurrently, except on the advice of a physician
6. Notify physician if tingling of the hands and feet, unusual tiredness or weakness, a feeling of heaviness in the legs, severe nausea, vomiting, abdominal pain or black stools (GI bleeding ) occurs
Pharmacology/ Pharmacokinetics:
Pharmacology:
The principal intracelluar cation, potassium is essential for maintenance of intracellular tonicity; transmission of nerve impulse; contractionof cardiac, skeletal and smooth muscle; and maintenance of normal renal function.
Pharmacokinetics:
Normally about 80 to 90% of potassium intake is excreted in urine with the remainder voided in stool and to a small ectent in prespiration. Kidneys do not conserve potassium well.
Pregnancy and lactation:
Pregnancy-
Give to a pregnant woman only if clearly indicated.
Lactation-
Excercise caution when administering to a nursing woman.
