Drug interactions
Cyproheptadine + Fentanyl iontophoretic transdermal system
Severity: Major
Cyproheptadine and Fentanyl iontophoretic transdermal system: major interaction.
Last updated Sources: US FDA label
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
Fentanyl delivered systemically is a potent opioid, and cyproheptadine adds sedation and anticholinergic effects. The combination may increase respiratory depression and drowsiness, particularly in opioid-naive or elderly patients.
What this interaction means in plain words
Cyproheptadine and Fentanyl iontophoretic transdermal system 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
Additive CNS and respiratory depression from opioid agonism and H1 antagonism, with additive anticholinergic effects.
What to do
Monitor sedation and respiratory rate, especially after starting or increasing doses. Prefer a non-sedating antihistamine where possible.
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?
Pro+ members
Unlock the full page
Create an account and start a Pro+ trial to unlock the full management advice for Cyproheptadine and Fentanyl iontophoretic transdermal system, the additional notes, the evidence detail and the whole-prescription interaction checker.
- Full clinical management advice
- Additional notes
- Evidence detail
- Interaction checker for a whole prescription
Try Pro+ free for 7 days on the web. No card needed.
References
Other interactions of Cyproheptadine
- Cyproheptadine + Isocarboxazid Contraindicated
- Cyproheptadine + Phenelzine Contraindicated
- Cyproheptadine + Tranylcypromine Contraindicated
- Alfentanil + Cyproheptadine Major
- Belladonna and opium + Cyproheptadine Major
- Benzhydrocodone / acetaminophen + Cyproheptadine Major
Frequently asked questions
Can I take Cyproheptadine with Fentanyl iontophoretic transdermal system?
MediHelp rates the interaction as major. Cyproheptadine and Fentanyl iontophoretic transdermal system 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. Fentanyl delivered systemically is a potent opioid, and cyproheptadine adds sedation and anticholinergic effects. The combination may increase respiratory depression and drowsiness, particularly in opioid-naive or elderly patients.
How serious is the interaction between Cyproheptadine and Fentanyl iontophoretic transdermal system?
MediHelp rates it major, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Monitor sedation and respiratory rate, especially after starting or increasing doses. Prefer a non-sedating antihistamine where possible.
What other medicines interact with Cyproheptadine?
MediHelp also lists interactions of Cyproheptadine with, for example, Isocarboxazid, Phenelzine, Tranylcypromine. The full list is on the Cyproheptadine page.
Full monographs, dosing and an interaction checker in the MediHelp app
Open the complete reference, check multi-drug interactions and use dosing tools in the MediHelp app.
