Lexiscan (regadenoson) is used for people who need to take a stress test to detect heart damage, but can't exercise on a treadmill or bike. It mimics blood flow to the heart during exercise. This medication is a part of nuclear stress test procedures that use a small amount of a radioactive substance to help take images of your heart. Lexiscan (regadenoson) is only available as an intravenous injection (IV) that's administered by a healthcare provider. This medication shouldn't be used (or is contraindicated) for people with certain types of heart blocks, so make sure your healthcare team knows your full medical history before undergoing any stress procedures.
Diagnosis of heart damage in people who can't exercise for a stress test
Lexiscan (regadenoson) is an adenosine receptor agonist that works as a diagnostic agent. It acts like adenosine, a chemical in your body that works as an energy source during activities. This raises the amount of blood flow to the heart. During a stress test, Lexiscan (regadenoson) mimics what happens during exercise (a rise in blood flow to the heart). This helps providers locate any specific areas of heart damage.
Source: DailyMed
Side effects that you should report to your care team as soon as possible:
Side effects that usually do not require medical attention (report these to your care team if they continue or are bothersome):
A good alternative for people who can't complete a stress test through exercise
A one-time dose given by a healthcare provider
Side effects usually go away within 15 to 30 minutes
Can usually drive yourself home after receiving this medication
Must be given as an injection through the vein (IV)
Requires close monitoring for serious side effects like heart problems and changes in blood pressure
Must avoid caffeine for at least 12 hours beforehand
Only approved for use in adults
Lexiscan (regadenoson) works very quickly, usually within a couple minutes. You might feel effects similar to what you experience during heavy or vigorous exercise, like shortness of breath, headache, chest discomfort, dizziness, or nausea.
Most of the common side effects of Lexiscan (regadenoson) begin soon after you get the injection, but they should go away within 15 minutes; headaches usually go away within 30 minutes.
You'll need to avoid caffeine (including coffee, tea, and energy drinks) for at least 12 hours before your stress test procedure with Lexiscan (regadenoson). Caffeine-containing foods, beverages, or products can make the medication work less well.
Make sure your provider knows about all of the medications you take at home. Your provider might tell you stop taking certain medications for a specific amount of time before your stress test to prevent drug interactions with Lexiscan (regadenoson). These medications can include aminophylline; theophylline; dipyridamole; and Aggrenox (aspirin / dipyridamole), a blood thinner used to prevent stroke.
Let your provider know if you're pregnant. Your provider will give you this medication only if absolutely necessary and only if the benefits outweigh the potential risk to your baby. There haven't been enough studies about using Lexiscan (regadenoson) in pregnant women to say whether or not it's safe.
Lexiscan (regadenoson) can cause some serious health issues. This risk may be even higher for certain groups. If this worries you, talk to your doctor or pharmacist about other options.
Risk factors: Heart disease | History of abnormal heart rhythm
Lexiscan (regadenoson) can cause heart problems, such as heart attack, abnormal heart rhythms, "heart block," and atrial fibrillation (AFib). Some of these heart problems can be life-threatening. Your healthcare team will keep a close eye on you during your stress test with Lexiscan (regadenoson). The team should have equipment and medications ready to treat any heart problems that might happen during or after your stress test.
Risk factors: Heart disease | History of high or low blood pressure
Lexiscan (regadenoson) can cause changes in blood pressure, usually within a few minutes to an hour of the IV injection. In some rare cases, changes in blood pressure has caused people to faint, have stroke-like symptoms, or have a seizure. Make sure your providers know your full medical history before you get this medication so they can check your risk for serious complications from changes in blood pressure. Your provider will monitor your blood pressure closely during the stress test, especially after you get the dose of Lexiscan (regadenoson).
Lexiscan (regadenoson) can make it hard for you to breathe since it can narrow (constrict) your airways. Before you get Lexiscan (regadenoson), tell your providers if you have any breathing conditions, such as asthma or chronic obstructive pulmonary disease (COPD). They'll have equipment and medications ready to treat any breathing problems that might happen after you receive Lexiscan (regadenoson).
Risk factors: History of seizure | Taking aminophylline
Lexiscan (regadenoson) can make you more likely to have a seizure, especially if you have a history of seizures to begin with. Make sure your provider knows if you have a seizure condition before your heart stress test procedure. Letting your providers know beforehand helps them be prepared to treat a seizure if necessary.
People have had strokes after getting Lexiscan (regadenoson). These strokes could be due to changes in blood pressure. Your provider will monitor your blood pressure closely during the stress test, especially after you get your dose of Lexiscan (regadenoson). Alert your provider right away if you develop sudden numbness or weakness, sudden confusion, trouble speaking, or trouble understanding speech. These can be symptoms of a stroke.
Allergic reactions to Lexiscan (regadenoson) are rare, but they can be life-threatening if they lead to heart problems, shortness of breath, throat tightness, dangerously low blood pressure, and anaphylaxis. Your healthcare team will have equipment nearby in case you experience any of these symptoms.
Lexiscan (regadenoson) is only available as an intravenous (IV) injection that's administered by a healthcare provider. The typical dose is 5 mL given as an injection through the vein over a 10-second period. Each 5 mL contains 0.4 mg of regadenoson.
Second- or third-degree heart block
Heart problems called sinus node dysfunction
Diagnosis of heart damage in people who can't exercise for a stress test
Certain types of irregular heart rhythms
Diagnosis of certain heart problems in people who can't exercise for a stress test
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