Licorice can lower potassium and raise blood pressure, which can make cardiac glycosides, potassium-depleting diuretics, and antihypertensive treatment harder to manage. It may also change exposure to warfarin, cyclosporine, corticosteroid replacement, and other medicines.

Use with caution. Healthcare professional review recommended before use.

Contraindications

Uncontrolled hypertension, edema, hypokalemia, or severe heart failure
High-dose or prolonged unsupervised use

Cautions

Raw licorice is still real licorice ... it can retain sodium, waste potassium, raise blood pressure, and complicate cardiac disease.
Because Gan Cao sits in so many formulas, cumulative exposure from multiple products is easy to underestimate.

Drug Interactions

Drug Class / Substrate	Mechanism	Severity	Source
Cardiac glycosides such as digoxin	Licorice-related potassium loss may increase cardiac glycoside toxicity.	Major	Memorial Sloan Kettering About Herbs
Loop and thiazide diuretics	Additive potassium loss may increase the risk of hypokalemia and rhythm problems.	Major	Memorial Sloan Kettering About Herbs
Antihypertensive medicines	Licorice can raise blood pressure and oppose the intended effect of treatment.	Major	Memorial Sloan Kettering About Herbs
Warfarin and related anticoagulants	Licorice may increase warfarin metabolism and clearance. Clinical relevance is not known, but reduced anticoagulant effect has been reported with a related medicine.	Moderate	Memorial Sloan Kettering About Herbs
Cyclosporine	Preclinical research found reduced oral bioavailability through P-glycoprotein and CYP3A4 activation.	Major	Memorial Sloan Kettering About Herbs
Cortisone or corticosteroid replacement	Licorice increased cortisol availability after cortisone acetate in patients with Addison's disease.	Moderate	Memorial Sloan Kettering About Herbs

This information is for educational purposes only and does not constitute medical advice. Always consult a qualified healthcare provider before using herbal medicines, especially if you take prescription medications.