High potassium community management

DGRefHelp - NHS Dumfries & Galloway
NHS Dumfries and Galloway

Hyperkalaemia is common in CKD, heart failure, and patients on RAASi. Most mild–moderate cases can be safely managed in the community provided the patient is well, has no AKI, and repeat bloods can be arranged.

Assessment

Exclude pseudohyperkalaemia first. Causes:

  • Delayed processing (>4h),
  • Haemolysis,
  • Fist clenching during venepuncture,
  • EDTA contamination,
  • Marked thrombocytosis or leucocytosis.

If asymptomatic with no obvious cause → repeat urgently in lithium heparin tube.

Is the patient acutely unwell or has AKI? If YES, refer to hospital regardless of K⁺ level.

Bloods: U&E, bicarbonate, glucose, magnesium, FBC; CK if rhabdomyolysis suspected.

ECG is not required — it does not change community management. 

Identify drivers:

Primary care management

SEVERE — K⁺ ≥6.5 mmol/L

  • Admit to hospital immediately (999) — life-threatening regardless of symptoms.
  • Continuous cardiac monitoring required in hospital.

MODERATE — K⁺ 6.0–6.4 mmol/L

  • Acutely ill or AKI → refer to hospital.
  • Otherwise → community management as below; repeat U&E within 1 working day (or 24 h if unexpected).

MILD — K⁺ 5.5–5.9 mmol/L

  • Acutely ill or AKI → consider hospital referral.
  • Otherwise → community management; repeat U&E within 14 days (or 3 days if unexpected).

 

*Out-of-hours repeat bloods: If a repeat U&E cannot be arranged within normal practice hours (evenings/weekends), the GP can call OOH via switchboard to arrange the repeat. Admission is not required solely because the repeat falls outside working hours.

Community management

  • Stop or reduce the drugs listed above. After stopping RAASi in CKD/HF, seek secondary care advice — a K⁺-binder may be indicated.
  • Diet: limit bananas, oranges, tomatoes, potatoes (boil and discard water), dried fruit, nuts, chocolate, avocado. Avoid all salt substitutes.
  • Consider Furosemide to enhance K⁺ excretion if fluid status allows.
  • Treat acidosis (Sodium bicarbonate in CKD with low HCO₃⁻)
  • Treat constipation.
  • Prevent recurrence: reinforce RAASi sick-day rules, monitor U&E in CKD (more often in CKD 4–5 or after RAASi titration), always ask about OTC salt substitutes.

Who to refer

999 / ED — immediate admission

  • Any K⁺ ≥6.5 mmol/L
  • K⁺ ≥6.0 mmol/L with symptoms
  • Any hyperkalaemia with acute illness or AKI
  • Suspected Addisonian crisis (hypotension, hyponatraemia, pigmentation)

Same-day medical / renal discussion

  • Rapidly rising K⁺ trend
  • Moderate hyperkalaemia with concerning AKI risk factors despite apparently well presentation

Routine renal / cardiology / endocrinology referral or advice request

  • CKD 3b–5 (not on dialysis) or HF with persistent K⁺ ≥6.0 on sub-optimal RAASi — for K⁺-binder consideration
  • Recurrent hyperkalaemia despite drug and dietary review
  • Suspected hypoaldosteronism or non-acute Addison's

Who not to refer

  • Confirmed pseudohyperkalaemia on repeat sample.
  • Mild K⁺ (5.5–5.9), clinically well, no AKI — drug/diet review and 14-day repeat.
  • Moderate K⁺ (6.0–6.4), clinically well, no AKI — community management appropriate; if out-of-hours, contact OOH via switchboard to arrange the 24h repeat.
  • Stable chronic mild hyperkalaemia in CKD where the cardiorenal benefit of RAASi outweighs risk and the patient is being monitored.
  • Diet- or supplement-driven mild rise that resolves with advice and removal of the source.

Editorial Information

Last reviewed: 03/06/2026

Next review date: 03/06/2028

Version: 1.0