Fluphenazine and Clonidine Transdermal Patch: Interaction Details
AI-assisted, pharmacist-reviewed · Source data updated Aug 8, 2026 · Sources: FDA labeling, DDInter 2.0, cited literature
Fluphenazine
No brand names on recordClonidine Transdermal Patch
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
An increased risk of dementia, induction or exacerbation of orthostatic regulation disturbances and an increased risk of sedation and somnolence
Interaction Deep Dive
Avoid concomitant use of cloNIDine and fluPHENAZine (CNS depressant) as it may potentiate the sedating effects1. Additionally, coadministration of cloNIDine with neuroleptics, such as fluPHENAZine 4, may result in orthostatic regulation disturbance induction or exacerbation 23. One case report described a man who experienced acute organic brain syndrome following the concurrent use of fluPHENAZine and cloNIDine. Symptoms disappeared upon the discontinuation of cloNIDine, but reappeared when cloNIDine therapy was reinstituted 5.
Why it happens (mechanism)
Unknown; additive sedative effects
Literature reports
1 report — tap to read
a) A 33-year old man presented with dementia which was found to be controllable with oral haloperidol. CloNIDine 0.1 mg twice daily was also instituted to control his hypertension. His psychosis cleared within 5 days. Due to compliance issues, the haloperidol was discontinued and fluPHENAZine decanoate 50 mg intramuscularly was administered every week. After 10 days, the patient became delirious, agitated, disoriented, and could not recognize people he knew. The cloNIDine was tapered off over 3 days, and within 24 hours his delirium began to clear. Within 72 hours, his mental status was at its previous level. Other antihypertensives failed to control his blood pressure, and cloNIDine was once again started. Within 72 hours he became confused and agitated. His mental status again cleared within 24 hours of stopping the cloNIDine 5.
Common questions
Can I take Fluphenazine and Clonidine Transdermal Patch together?
An increased risk of dementia, induction or exacerbation of orthostatic regulation disturbances and an increased risk of sedation and somnolence Always confirm with your pharmacist or prescriber before making any change.
How serious is the Fluphenazine and Clonidine Transdermal Patch interaction?
It is rated moderate. Can be significant — usually manageable with 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 "probable". Good supporting evidence, though not definitively proven.
Questions for your pharmacist
- Does my dose of Fluphenazine or Clonidine Transdermal Patch 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 anything you'd monitor while I'm on both?
References (5)
- Product Information: ONYDA(TM) XR extended release suspension, clonidine hydrochloride extended release suspension. Tris Pharma, Inc (Per FDA), Monmouth Junction, NJ, 2024.
- Product Information: Catapres(R) oral tablets, clonidine HCl oral tablets. Boehringer Ingelheim Pharmaceuticals, Inc. (per Manufacturer), Ridgefield, CT, 2012. DailyMed
- Product Information: Catapres-TTS(R) transdermal system, clonidine transdermal system. Boehringer Ingelheim Pharmaceuticals, Inc. (per Manufacturer), Ridgefield, CT, 2012. DailyMed
- Product Information: FLUPHENAZINE HCl oral film coated tablet, fluphenazine HCl oral film coated tablet. Mylan Pharmaceuticals, Inc. (per DailyMed), Morgantown, WV, 2010.
- Allen RM & Flemenbaum A: Delirium associated with combined fluphenazine-clonidine therapy. J Clin Psychiatry 1979; 40:236-237.
Keep reading about Fluphenazine
Keep reading about Clonidine Transdermal Patch
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