MODERATE — Monitor Closely
🟡 CAUTION — Licorice root causes pseudoaldosteronism (sodium retention, potassium wasting, blood pressure elevation) that directly opposes Diltiazem. Avoid licorice root if taking antihypertensive medications, or use DGL (deglycyrrhizinated licorice) which lacks this effect.
Evidence level: STRONG
Licorice root causes sodium and water retention through pseudoaldosteronism, raising blood pressure. Diltiazem relaxes blood vessels and slows heart rate by blocking calcium channels, but it cannot prevent the volume expansion and potassium loss that licorice triggers through mineralocorticoid receptor activation.
Glycyrrhizin in licorice root inhibits 11-beta-hydroxysteroid dehydrogenase type 2, causing cortisol to activate mineralocorticoid receptors (pseudoaldosteronism). This causes sodium retention, potassium wasting, and blood pressure elevation — directly opposing the antihypertensive action of Diltiazem.
Avoid licorice root while on Diltiazem. Diltiazem is a non-dihydropyridine calcium channel blocker also used for heart rate control in atrial fibrillation. The potassium depletion from licorice increases arrhythmia risk, which is particularly dangerous if Diltiazem was prescribed specifically to manage your heart rhythm. Diltiazem also inhibits CYP3A4, so discuss any supplement changes with your doctor. Use DGL licorice instead.
Be consistent with how you take Diltiazem relative to meals — take it with food or without food consistently each day. Licorice Root — sudden large changes in diet composition can affect how your body processes many medications. Grapefruit, leafy greens, and high-fiber foods are the most common food-drug interaction culprits.
Higher risk for: elderly, those with liver or kidney impairment, polypharmacy (5+ medications), recent medication changes, or those with multiple chronic conditions. Consult your pharmacist for specific risk factors.
Rising blood pressure despite medication, headache, swelling in legs/ankles, muscle weakness or cramps, irregular heartbeat (from low potassium).
No urgent need to discuss, but always keep your doctor informed of your full supplement and medication list. An up-to-date list helps them make the best treatment decisions.
Adjust the timing or quantity of Licorice Root relative to your medication. Maintain consistent daily intake rather than large sporadic amounts. Your pharmacist can advise on specific timing windows.
Licorice root causes sodium and water retention through pseudoaldosteronism, raising blood pressure. Diltiazem relaxes blood vessels and slows heart rate by blocking calcium channels, but it cannot prevent the volume expansion and potassium loss that licorice triggers through mineralocorticoid receptor activation.
Be consistent with how you take Diltiazem relative to meals — take it with food or without food consistently each day. Licorice Root — sudden large changes in diet composition can affect how your body processes many medications. Grapefruit, leafy greens, and high-fiber foods are the most common food-drug interaction culprits.
Rising blood pressure despite medication, headache, swelling in legs/ankles, muscle weakness or cramps, irregular heartbeat (from low potassium).
Adjust the timing or quantity of Licorice Root relative to your medication. Maintain consistent daily intake rather than large sporadic amounts. Your pharmacist can advise on specific timing windows.
No urgent need to discuss, but always keep your doctor informed of your full supplement and medication list. An up-to-date list helps them make the best treatment decisions.
Or browse the full interaction database (121,000+ pairs).