While no specific interactions (positive or negative) between the herb ephedra and conventional medications have been reported, the active ingredients of ephedra, ephedrine, and pseudoephedrine 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 -- Amphetamine and amphetamine derivatives (such as dextroamphetamine sometimes used for attention deficit hyperactivity disorder and narcolepsy) should not be used with ephedra. Ephedra may cause increased effects of amphetamines on the body, such as increased heart rate and blood pressure.
• Antidepressants -- Ephedra may interact with 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 and blood-thinning medications -- Ephedra may increase bleeding in sensitive individuals, such as those taking aspirin or other blood thinning medications.
• Blood pressure medications -- Ephedra may interact with blood pressure lowering medications, particularly clonidine.
• Caffeine and guarana (a caffeine-containing herb)
• Narcotics -- Ephedra may interact with narcotices prescribed for pain, such as morphine and codeine; codeine may also be prescribed for cough.
• Theophylline -- Ephedra may interact with theophylline (used for asthma).