While no specific interactions (positive or negative) between the herb ephedra and conventional medications have been reported in the literature, the active ingredients of ephedra, ephedrine and pseudoephedrine (available in a number of over-the-counter and prescription products for weight loss or nasal congestion), have been associated with several serious drug interactions. We may assume, for safety's sake, that those drugs that interact with ephedra's active ingredients may also interact with the herb ephedra. Medications for which there are well-documented interactions with ephedra's active ingredients include:

• Amphetamine and Amphetamine derivatives (such as dextroamphetamine sometimes used for attention deficit hyperactivity disorder and narcolepsy)
• Antidepressants; namely, those in the class of tricyclics (such as clomipramine, desipramine, doxepin, imipramine, and nortriptyline) and monoamine oxidase inhibitors (MAOIs, including phenelzine and trancylcypromine)
• Aspirin 
• Blood Pressure Medications, particularly clonidine
• Caffeine and Guarana (a caffeine-containing herb)
• Narcotics, such as morphine and codeine, prescribed for pain; codeine may also be prescribed for cough
• Phenylpropanolamine (also known as norephedrine, found in certain supplements); formerly in many over the counter and prescription remedies for cough and cold; was removed from the market by the FDA because of risk of bleeding stroke. Norephedrine found in certain dietary supplements for weight loss can cause liver damage.
• Theophylline (used for asthma)