Drug interactions
Fentanyl intranasal + Promethazine
Severity: Major
Fentanyl intranasal and Promethazine: major 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
The concurrent use of promethazine and intranasal fentanyl can lead to enhanced sedation and respiratory depression. This combination may significantly impair cognitive and motor functions, increasing the risk of adverse effects.
What this interaction means in plain words
Fentanyl intranasal and Promethazine can interact in a way that may be serious. Using them together is sometimes necessary, but it needs a deliberate decision by the prescriber, a plan for monitoring, and clear advice on the warning signs to watch for.
Why it happens
Both drugs possess sedative properties, with promethazine acting as an antihistamine and fentanyl being an opioid analgesic. Their combined effects can lead to additive sedation and respiratory suppression.
What to do
Patients receiving both medications should be closely monitored for signs of excessive sedation and respiratory distress. Consider alternative therapies if possible, especially in individuals with pre-existing respiratory conditions or those who are sensitive to sedative effects.
What to ask your pharmacist
- Does the benefit of taking both outweigh the risk in my case?
- Do I need any blood test, ECG or other check while on both?
- What early warning signs should I watch for, and what should I do if they appear?
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Other interactions of Promethazine
- Cabergoline + Promethazine Contraindicated
- Dopamine + Promethazine Contraindicated
- Ibutilide + Promethazine Contraindicated
- Pimozide + Promethazine Contraindicated
- Promethazine + Thioridazine Contraindicated
- Alfentanil + Promethazine Major
Frequently asked questions
Can I take Fentanyl intranasal with Promethazine?
MediHelp rates the interaction as major. Fentanyl intranasal and Promethazine can interact in a way that may be serious. Using them together is sometimes necessary, but it needs a deliberate decision by the prescriber, a plan for monitoring, and clear advice on the warning signs to watch for. The concurrent use of promethazine and intranasal fentanyl can lead to enhanced sedation and respiratory depression. This combination may significantly impair cognitive and motor functions, increasing the risk of adverse effects.
How serious is the interaction between Fentanyl intranasal and Promethazine?
MediHelp rates it major, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Patients receiving both medications should be closely monitored for signs of excessive sedation and respiratory distress. Consider alternative therapies if possible, especially in individuals with pre-existing respiratory conditions or those who are sensitive to sedative effects.
What other medicines interact with Promethazine?
MediHelp also lists interactions of Promethazine with, for example, Cabergoline, Dopamine, Ibutilide. The full list is on the Promethazine page.
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