Potassium deficiency can destabilize the heart’s electrical system, so hypokalemia is a well‑known trigger for cardiac arrhythmias and can present with palpitations, “skipped beats,” or more dangerous rhythm disturbances even before other symptoms are obvious. As serum potassium drops, characteristic ECG changes (flattened or inverted T waves, ST‑segment depression, prominent U waves, and QT‑interval prolongation) reflect impaired repolarization, which can progress to premature ventricular contractions, atrial fibrillation, ventricular tachycardia, torsade de pointes, or even ventricular fibrillation and cardiac arrest in severe cases. Observational data show that hypokalemia and even low‑normal potassium levels increase the risk of ventricular arrhythmias and sudden cardiac death in people with underlying heart disease, highlighting the importance of monitoring and promptly correcting potassium deficits in hospitalized and high‑risk patients. This medication is commonly used for Hypertension.
Krijthe BP, Heeringa J, Kors JA, Hofman A, Franco OH, Witteman JC, Stricker BH. Serum potassium levels and the risk of atrial fibrillation: the Rotterdam Study. Int J Cardiol. 2013 Oct 15;168(6):5411-5.Jeejeebhoy KN, Chu RC, Marliss EB, Greenberg GR, Bruce-Robertson A. Chromium deficiency, glucose intolerance, and neuropathy reversed by chromium supplementation, in a patient receiving long-term total parenteral nutrition. Am J Clin Nutr. 1977 Apr;30(4):531-8. Wang XD, Wang Y, Liu J, Yao JW, Zhang J, Zhang YN. Prognosis of Older Adult Patients Suffering from Atrial Fibrillation and Hypokalemia. Clin Interv Aging. 2023;18:1363-1371. Federico Bernardo Rossi, Ambra Sammarco, Teresa Maria Seccia, Potassium and aldosterone as determinants of new-onset atrial fibrillation, European Heart Journal, 2026.
Some side effects may be linked to nutrient depletion caused by this medication.
An increased excretion of potassium can occur in people taking calcium channel blocker drugs like felodipine. Supplementation may need to be considered if blood levels of potassium are low.
Studies suggest that Felodipine, a type of calcium channel blocker (CCB), may increase the excretion of calcium in the urine. While the long-term effects on bone health are unclear, some healthcare professionals suggest calcium supplementation for patients taking felodipine, especially those at higher risk of osteoporosis.
Research suggests that Felodipine, a type of calcium channel blocker (CCB), may increase the excretion of magnesium in the urine. This can potentially lead to magnesium deficiency. Studies have shown an increase in fractional excretion of magnesium following felodipine treatment, and the drug may also alter how magnesium moves across red blood cell membranes. Therefore supplementation with magnesium should be considered when on this therapy.