Drug interactions
Iobenguane i + Naphazoline
Severity: Moderate
Iobenguane i and Naphazoline: moderate interaction.
Last updated
For healthcare professionals — reference only. This page is a brief summary, not medical advice and not a substitute for official labeling or clinical judgement. Always verify before prescribing or dispensing.
Summary
Naphazoline is a sympathomimetic vasoconstrictor that may interfere with the uptake of iobenguane into adrenergic tissue. Reduced uptake could lower the imaging quality or therapeutic efficacy of iobenguane I-131. The effect is mainly predicted from mechanism, and systemic exposure from topical forms is low.
What this interaction means in plain words
Iobenguane i and Naphazoline can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken.
Why it happens
Sympathomimetics may compete with iobenguane for the norepinephrine transporter or alter catecholamine storage, reducing tumor uptake of the radiopharmaceutical.
What to do
Avoid systemic naphazoline-containing products around iobenguane dosing, stopping them for several half-lives beforehand and for at least 7 days after each dose per product labeling. Topical ocular or nasal use with minimal absorption is unlikely to matter, but prefer a non-interfering alternative.
What to ask your pharmacist
- Should I take them at different times of day?
- Does the dose of either medicine need to change?
- Is there anything I should avoid, such as alcohol or certain foods, while on both?
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Other interactions of Naphazoline
- Naphazoline + Safinamide Moderate
- Naphazoline + Solriamfetol Moderate
- Naphazoline + Zavegepant intranasal Moderate
- Naphazoline + Nicotine Minor
- Naphazoline + Nicotine intranasal Minor
Frequently asked questions
Can I take Iobenguane i with Naphazoline?
MediHelp rates the interaction as moderate. Iobenguane i and Naphazoline can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken. Naphazoline is a sympathomimetic vasoconstrictor that may interfere with the uptake of iobenguane into adrenergic tissue. Reduced uptake could lower the imaging quality or therapeutic efficacy of iobenguane I-131. The effect is mainly predicted from mechanism, and systemic exposure from topical forms is low.
How serious is the interaction between Iobenguane i and Naphazoline?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Avoid systemic naphazoline-containing products around iobenguane dosing, stopping them for several half-lives beforehand and for at least 7 days after each dose per product labeling. Topical ocular or nasal use with minimal absorption is unlikely to matter, but prefer a non-interfering alternative.
What other medicines interact with Naphazoline?
MediHelp also lists interactions of Naphazoline with, for example, Safinamide, Solriamfetol, Zavegepant intranasal. The full list is on the Naphazoline page.
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