Theophylline (drug interactions)
Theophylline is a respiratory medication historically used to treat asthma and other respiratory diseases, although its prevalence has declined due to the emergence of newer treatments with fewer side effects. Understanding drug interactions with theophylline is crucial, as various substances can significantly affect its efficacy and safety. Key interactions include certain prescription medications, herbal supplements like St. John's wort, and dietary components such as caffeine and guarana, which may reduce theophylline's effectiveness or increase the risk of toxicity.
Cayenne and ipriflavone are also noted for potentially elevating theophylline levels in the body, which could lead to adverse effects. Additionally, high intake of tannin-rich foods, charbroiled meat, and cruciferous vegetables may impair the absorption of theophylline. As theophylline interacts with many drugs treating unrelated health issues, patients are advised to consult healthcare professionals before combining it with other medications. Overall, awareness of these interactions is essential for safe and effective use of theophylline in managing respiratory conditions.
Theophylline (drug interactions)
DEFINITION: Once among the most common treatments for asthma, theophylline is no longer widely used, having been replaced by drugs that cause fewer side effects.
INTERACTIONS: Various prescription medications, cayenne, ipriflavone, St. John’s wort, ephedra, guarana, tannin-containing herbs, vitamin B6
TRADE NAMES: Theo-24, Elixophyllin
DRUGS IN THIS FAMILY: Aminophylline (generic), choline theophyllinate (Not available in US)
Vitamin B6
Effect: Supplementation Possibly Helpful
Theophylline appears to impair the normal conversion of vitamin B6 into the more active substance pyridoxal 5’-phosphate (PLP). These findings have led some researchers to suspect that some of theophylline's many side effects could be caused, in part, by interference with B6 activity. Indeed, one study found that B6 supplements might help reduce theophylline-induced tremors.
St. John’s Wort
Effect: Possible Interference with Action of Drug
Evidence suggests that the herb St. John’s wort can lower blood levels of theophylline, making it less effective.
Cayenne
Effect: Possible Increased Risk of Toxicity
Oral cayenne might increase the absorption of theophylline, leading to an increased risk of theophylline toxicity.
Ipriflavone
Effect: Possible Increased Risk of Toxicity
Like cayenne, the supplement ipriflavone may increase levels of theophylline in the body, possibly increasing the risk of toxicity.
Other interactions
By the twenty-first century, researchers had discovered hundreds of drugs that interact with theophylline, with interactions ranging from major to minor. Many of these medications treat conditions for which theophylline is not advised, including gastroesophageal reflux disease (GERD), renal dysfunction, seizure disorders, and tachyarrhythmias. Patients should not consume excessive caffeine while taking theophylline, and they should avoid guarana. Other herbs and supplements that interact with theophylline include ephedra, which may stimulate the central nervous system and cause rapid heartbeat. Tannins, like those found in tea, can decrease the absorption of theophylline, as can charbroiled meat and cruciferous vegetables. Patients taking certain antibiotics, seizure medications, and heartburn medications should consult their doctor before adding theophylline.
Bibliography
Bartel, P. R., et al. "Vitamin B6 Supplementation and Theophylline-Related Effects in Humans." American Journal of Clinical Nutrition, vol. 60, 1994, pp. 93-99.
Jobst, K. A., et al. "Safety of St. John’s Wort (Hypericum perforatum)." The Lancet, vol. 355, 2000, pp. 575.
Kahn, Sonia. "Theophylline Interactions." The Pharmaceutical Journal, 10 July 2014, pharmaceutical-journal.com/article/ld/theophylline-interactions. Accessed 11 Sept. 2024.
Nebel, A., R. K. Baker, and D. J. Kroll. "Potential Metabolic Interaction Between Theophylline and St. John’s Wort." Annals of Pharmacotherapy, vol. 33, no. 4, 1999, p. 502.
Shimizu, T., et al. "Theophylline Attenuates Circulating Vitamin B6 Levels in Children with Asthma." Pharmacology, vol. 49, 1994, pp. 392-397.
"Theophylline." MedlinePlus, 15 Nov. 2019, medlineplus.gov/druginfo/meds/a681006.html. Accessed 11 Sept. 2024.
"Theophylline (Oral Route) Description and Brand Names." Mayo Clinic, 1 Sept. 2024, www.mayoclinic.org/drugs-supplements/theophylline-oral-route/description/drg-20073599. Accessed 11 Sept. 2024.
“Theophylline Oral: Uses, Side Effects, Interactions, Pictures, Warnings & Dosing.” WebMD, www.webmd.com/drugs/2/drug-3591-3076/theophylline-oral/theophylline-sustained-release-oral/details. Accessed 11 Sept. 2024.