Do Any Herbs Interact With Lexiscan (Regadenoson)?

Answer

Thanks for reaching out! This is an interesting question based on the fact we're talking about a drug that lasts in the body for an extremely short amount of time.

Lexiscan (regadenoson) is used for imaging purposes during a stress test of the heart. It is administered intravenously and will be completely metabolized and eliminated from your system a few hours after your dose.

Nevertheless, there is an interaction that is important to know about, and that is with any caffeine-containing products. This would certainly include some herbals that naturally contain caffeine.

Avoid Caffeine-Containing Products With Regadenoson

In terms of dietary supplements, you want to avoid taking anything with caffeine or similar stimulants, and this would include things like green tea and coffee, with regadenoson. Per the prescribing information for the drug:

Patients should be instructed to avoid consumption of any products containing methylxanthines, including caffeinated coffee, tea or other caffeinated beverages, caffeine-containing drug products, aminophylline and theophylline for at least 12 hours before a scheduled radionuclide MPI (Myocardial Perfusion Imaging).

The reason why it is recommended to avoid caffeine and caffeine-like drugs is that they may impair the vasodilatory effects of regadenoson (i.e., the blood vessels may not dilate enough). This could ultimately affect the diagnostic conclusions of the stress test.

What About Other Herbals?

Other than caffeine, there are no studies that I am aware of that have evaluated herbal supplements with regadenoson. However, it stands to reason that any herbal that naturally contains caffeine, or has a vasoconstricting effect (like caffeine can have), should not be taken if you are scheduled to have a dose of regadenoson. So, this would include herbs that Butcher's Broom, which can cause vasoconstriction and the following herbs that naturally contain some caffeine:

• Guarana
• Cacao
• Tea leaves
• Kola Nut
• Yerba Mate
• Yaupon

Now, due to the lack of studies on taking specific herbals with regadenoson, it may be prudent to stop taking them at least a day before you are scheduled to get regadenoson, even if they don't contain caffeine. This recommendation is just to keep you on the safe side as you don't want to take anything that can interfere with your test.

Lastly, the manufacturer's website of regadenoson specifically recommends against all caffeine, chocolate, and diet supplements for at least 12 hours before a test:

Regadenoson lasts such a short time in your system, you likely can safely resume taking your herbals the next day or simply after your test.

Final Words

I highly recommend speaking with your doctor regarding what medications and herbs are safe for your particular medical situation.

As mentioned, you certainly want to avoid caffeine and similar stimulants, and any supplement that contains them.

In addition to things like green tea, many diet, and weight loss supplements contain green tea extract and other ingredients that are a source of caffeine (like guarana). Those should be avoided with regadenoson.

Thanks for reaching out and please do so again anytime!