Sodium Bicarbonate

How it works

Bicarbonate acts as a buffer that neutralises excess hydrogen ions, raising serum and urinary pH and helping to counter the metabolic acidosis that accompanies declining renal function.

Prescribing in practice

• The sodium load can worsen hypertension, fluid retention and heart failure and may aggravate oedema in CKD, so blood pressure and fluid status must be watched, particularly in those with cardiac disease.
• Overcorrection can cause metabolic alkalosis and contribute to hypokalaemia, and it may reduce ionised calcium.
• Its alkalinising effect alters urinary pH and can change the excretion of some other drugs, so review interactions.

Monitoring

Monitor serum bicarbonate, electrolytes, blood pressure and fluid status during treatment.

Counselling the patient

• Take it as directed for your kidney function and do not double up doses.
• Report increasing ankle swelling or breathlessness.
• Attend for blood tests to check your bicarbonate and potassium levels.

Evidence & guidelines

Evidence indicates correcting acidosis may slow CKD progression and improve nutritional status, and current prescribing references and the SPC guide oral bicarbonate use.