Determine when to use MRAs in PA patients with controlled blood pressure and normal potassium
STEP 1 — Gather Information
Confirm PA diagnosis via positive screening (ARR ≥200, PAC ≥60 pg/mL) and a confirmatory test; document office/home BP (<130/80 mmHg), serum potassium (3.5‑5.0 mmol/L), current antihypertensives, baseline eGFR and urinalysis.
STEP 2 — Rule In / Rule Out
Is the patient diagnosed with primary aldosteronism?
- No → Manage hypertension per usual guidelines; MRA not indicated for PA.
- Yes → Proceed to step 3.
STEP 3 — Classify or Stratify
Assess for contraindications: serum K >5.0 mmol/L, eGFR <30 mL/min/1.73 m², pregnancy (unless spironolactone after first trimester with obstetric advice), or concomitant use of potassium‑sparing agents with eplerenone/esaxerenone.
- Contraindication present → Avoid MRA; consider alternative antihypertensives or specialist referral.
- No contraindication → Proceed to step 4.
STEP 4 — Decide
Initiate MRA: spironolactone 25‑50 mg daily, eplerenone 2.5‑5 mg daily, or esaxerenone 1.25‑2.5 mg daily. Re‑check serum potassium, creatinine, and BP at 4‑6 weeks; continue long‑term to prevent target organ damage.
Clinical Guardrails / Mimics / Pitfalls
Do not start MRA if K >5.0 mmol/L or eGFR <30 mL/min/1.73 m²; avoid combining eplerenone/esaxerenone with potassium supplements or potassium‑sparing diuretics; monitor men for gynecomastia with spironolactone; do not discontinue MRA solely because BP and K are well controlled.
Concrete Clinical Example
A 58‑year‑old woman with PA confirmed by AVS, BP 128/76 mmHg on amlodipine 5 mg daily, K 4.2 mmol/L, asks whether she can stop low‑dose spironolactone. She continues MRA; at 4‑week follow‑up K is 4.4 mmol/L, BP stable, no adverse events.
Source: Japan Endocrine Society clinical practice guideline for the diagnosis and management of primary aldosteronism 2021, Japan Endocrine Society, 2021