Figure 1From: A pilot study of the effect of spironolactone therapy on exercise capacity and endothelial dysfunction in pulmonary arterial hypertension: study protocol for a randomized controlled trial Serum potassium and creatinine monitoring schedule. *Participants with potassium level ≥5.3 at week 1 will not be eligible for dose increase at 8 weeks. **Throughout the study, participants with potassium level >5.0 will undergo dietary counseling regarding a low potassim diet. Cr, creatinine; K, potassium; labs, laboratory tests.Back to article page