Drug interactions
Difelikefalin + Promethazine
Severity: Moderate
Difelikefalin and Promethazine: 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
Difelikefalin can cause somnolence and dizziness, and promethazine adds sedating effects. Together they may cause excessive drowsiness and falls, particularly in dialysis patients who are often frail.
What this interaction means in plain words
Difelikefalin and Promethazine 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.
Difelikefalin belongs to Dermatology; Promethazine belongs to Respiratory.
Why it happens
Additive CNS depressant effects from kappa-opioid agonism and H1 antagonism.
What to do
Monitor for excessive sedation and dizziness and counsel on fall prevention; reduce the promethazine dose if drowsiness occurs.
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 Promethazine
- Cabergoline + Promethazine Contraindicated
- Dopamine + Promethazine Contraindicated
- Ibutilide + Promethazine Contraindicated
- Pimozide + Promethazine Contraindicated
- Promethazine + Thioridazine Contraindicated
- Alfentanil + Promethazine Major
Other interactions of Difelikefalin
- Acetazolamide + Difelikefalin Moderate
- Alprazolam + Difelikefalin Moderate
- Amantadine + Difelikefalin Moderate
- Amitriptyline + Difelikefalin Moderate
- Amobarbital + Difelikefalin Moderate
- Asenapine + Difelikefalin Moderate
Frequently asked questions
Can I take Difelikefalin with Promethazine?
MediHelp rates the interaction as moderate. Difelikefalin and Promethazine 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. Difelikefalin can cause somnolence and dizziness, and promethazine adds sedating effects. Together they may cause excessive drowsiness and falls, particularly in dialysis patients who are often frail.
How serious is the interaction between Difelikefalin and Promethazine?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Monitor for excessive sedation and dizziness and counsel on fall prevention; reduce the promethazine dose if drowsiness occurs.
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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