A test tube study demonstrated that the bronchodilating effects of salbutamol, a drug with similar actions in the lung to ephedrine, were significantly increased by the addition of forskolin, the active component of the herb Coleus forskohlii. ¹ The results of this preliminary research suggest that the combination of forskolin and beta-agonists (like ephedrine) might provide an alternative to raising the doses of the beta-agonist drugs as they lose effectiveness. Until more is known, coleus should not be combined with ephedrine without the supervision of a doctor.

Tannins are a group of unrelated chemicals that give plants an astringent taste. Herbs containing high amounts of tannins may interfere with the absorption of ephedrine or pseudoephedrine taken by mouth.² Herbs containing high levels of tannins include green tea, black tea, uva ursi (Arctostaphylos uva-ursi), black walnut (Juglans nigra), red raspberry (Rubus idaeus), oak (Quercus spp.), and witch hazel (Hamamelis virginiana).

Ephedra is the plant from which ephedrine was originally isolated. Until 2004, ephedra—also called ma huang—was used in many herbal products, including supplements promoted for weight loss. To prevent potentially serious interactions, people taking ephedrine or pseudoephedrine should avoid using ephedra-containing drug products and should read product labels carefully for ma huang or ephedra content. Native North American ephedra, sometimes called Mormon tea, contains no ephedrine.

Caffeine, which is found in coffee, tea, chocolate, guaraná (Paullinia cupana), and some nonprescription and supplement products, can amplify the side effects of ephedrine and pseudoephedrine. People should avoid combination products containing ephedrine/pseudoephedrine/ephedra and caffeine.

Foods that acidify the urine may increase the elimination of ephedrine from the body, potentially reducing the action of the drug.³ Urine-acidifying foods include eggs, peanuts, meat, chicken, wheat-containing foods, and others.

Foods that alkalinize the urine may slow the elimination of ephedrine from the body, potentially increasing the actions and side effects of the drug.⁴ Urine-alkalinizing foods include dairy products, nuts, vegetables (except corn and lentils), most fruits, and others.