Potassium replacement

Potassium chloride

Brand names: Sando-K, Slow-K, Kay-Cee-L

Adult dose

Dose: Mild PO: 2–4 effervescent tabs (Sando-K 12 mmol K+) divided. Severe IV: 10–20 mmol/h via central line, max 40 mmol/h with cardiac monitoring; usually 40 mmol in 1L NaCl 0.9% over 4h peripherally

Route: PO/IV

Frequency: per indication

Dose adjustments

Renal

Use cautiously; avoid if hyperkalaemic or anuric

Clinical pearls

NEVER bolus IV — fatal arrhythmia
Use pre-prepared bags; max 40 mmol/L peripherally

Contraindications

Hyperkalaemia
Severe renal impairment
Untreated Addison's
Concurrent K-sparing diuretic / ACEi without monitoring

Side effects

Cardiac arrhythmia (bolus IV — never)
Phlebitis (peripheral IV)
GI ulceration (high-dose PO)
Hyperkalaemia

Interactions

ACEi/ARB
K-sparing diuretics
Spironolactone
Trimethoprim
Heparin

Monitoring

K+
ECG
Renal function

Reference: BNF; NICE NG29; UK guidelines; https://bnf.nice.org.uk/drugs/potassium-chloride/. Verify against your local formulary and the latest BNF before prescribing.

Curated clinical cross-links plus same-class fallbacks.

Calculators

Pathways