As pleurisy root and other plants in the Aesclepius genus contain cardiac glycosides, it is best to avoid use of pleurisy root with heart medications such as beta-blockers.

Some beta-adrenergic blockers (called “nonselective” beta blockers) decrease the uptake of potassium from the blood into the cells, leading to excess potassium in the blood, a potentially dangerous condition known as hyperkalemia. People taking beta-blockers should therefore avoid taking potassium supplements, or eating large quantities of fruit (e.g., bananas), unless directed to do so by their doctor.

The active ingredients in yohimbine can block the actions of brimonidine in certain human tissues, thus reducing the drug’s beneficial effects. Adequate human studies involving the eye are lacking, and until more information is available, yohimbine should be avoided in people using brimonidine.