Iobenguane I 123 and Metaproterenol: Interaction Details
AI-assisted, pharmacist-reviewed · Source data updated Aug 8, 2026 · Sources: FDA labeling, DDInter 2.0, cited literature
Metaproterenol
Iobenguane I 123
No brand names on record
How we grade severity & evidence
Severity levels
- Contraindicated: These should generally not be used together.
- Major: Potentially serious — often needs a change or close monitoring.
- Moderate: Can be significant — usually manageable with monitoring.
- Minor: Usually limited clinical impact.
Evidence grades
- Established: Well documented — supported by controlled studies or strong clinical data.
- Probable: Good supporting evidence, though not definitively proven.
- Suspected: Some evidence suggests this interaction, but it is not well established.
- Possible: Limited or conflicting evidence; the interaction may occur.
- Theoretical: Predicted from the drugs' pharmacology; not yet confirmed in people.
Ratings come from the documented interaction literature and are reviewed by a pharmacist. They describe the documented risk of the combination, not what will necessarily happen to you — your dose, timing, and health picture all matter.
What happens
Potential for false negative imaging results
Interaction Deep Dive
Iobenguane is similar in structure to the neurotransmitter norepinephrine and is taken up by the norepinephrine transporter in adrenergic nerve terminals. It is stored in the presynaptic storage vesicles. Iobenguane will accumulate in adrenergically innervated tissues and labeling iobenguane with the isotope iodine 123 will provide images of specific organs and tissues. Sympathomimetic amines that inhibit norepinephrine uptake, such as ephedrine, isoproterenol, phenylephrine, phenylpropanolamine, and pseudoephedrine, may interfere with the clinical efficacy of iobenguane I 123. Increasing the dose of iobenguane I 123 will not overcome any potential norepinephrine uptake inhibition by these drugs. If iobenguane I 123 imaging is necessary, discontinue this drug for at least 5 biological half-lives when clinically feasible1.
Why it happens (mechanism)
Decreased norepinephrine uptake by sympathomimetic amines
Common questions
Can I take Iobenguane I 123 and Metaproterenol together?
Potential for false negative imaging results Always confirm with your pharmacist or prescriber before making any change.
How serious is the Iobenguane I 123 and Metaproterenol interaction?
It is rated major. Potentially serious — often needs a change or close monitoring.
How quickly could this interaction happen?
The documented onset is "unspecified". The timing of this interaction is not well characterized.
How strong is the evidence for this interaction?
The evidence is graded "theoretical". Predicted from the drugs' pharmacology; not yet confirmed in people.
Questions for your pharmacist
- Does my dose of Iobenguane I 123 or Metaproterenol need adjusting while I take them together?
- What symptoms should prompt me to call you or my prescriber right away?
- Does the timing of my doses matter for this combination?
- Is there a safer alternative to one of these medications for me?
References (1)
- Product Information: AdreView(TM) intravenous injection, iobenguane I 123 intravenous injection. GE Healthcare (per FDA), Arlington Heights, IL, 2013. DailyMed
Keep reading about Metaproterenol
Keep reading about Iobenguane I 123
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