What the FDA labels say about taking them together
Fluconazole and guanfacine
Guanfacine's FDA label of June 23, 2025 names fluconazole in its drug interactions section; the fluconazole labels PlainMeds reads (2) do not name guanfacine. The guanfacine label: “Consider dose reduction”
Check it at the source: the fluconazole FDA label on DailyMed (effective April 7, 2026, Zydus Pharmaceuticals (USA) Inc.); the guanfacine FDA label on DailyMed (effective June 23, 2025, Takeda Pharmaceuticals America, Inc.).
What does the fluconazole label say about guanfacine?
Fluconazole's label (effective April 7, 2026) and its 1 other brand-application label do not name guanfacine in these sections. A label lists what its studies and reports found; it is not a complete list.
Source: FDA drug label (fluconazole), Zydus Pharmaceuticals (USA) Inc., effective April 7, 2026 (SPL set d1364455-1537-46d4-b093-38cca3be778f), via openFDA; the full label on DailyMed
What does the guanfacine label say about fluconazole?
Guanfacine label, drug interactionsConcomitant Drug Name or Drug Class: Strong and moderate CYP3A4 inhibitors, e.g., ketoconazole, fluconazole; Clinical Rationale and Magnitude of Drug Interaction: Guanfacine is primarily metabolized by CYP3A4 and its plasma concentrations can be significantly affected resulting in an increase in exposure; Clinical Recommendation: Consider dose reduction [see ]
Source: FDA drug label (Intuniv), Takeda Pharmaceuticals America, Inc., effective June 23, 2025 (SPL set b972af81-3a37-40be-9fe1-3ddf59852528), via openFDA; the full label on DailyMed
These are the labels' own sentences. PlainMeds does not grade interactions; a pharmacist or prescriber can say what they mean for one person's medicines.
Both medicines on the record
| Fluconazole | Guanfacine | |
|---|---|---|
| Labeled for | Fungal infections, Urinary tract infections | ADHD, High blood pressure |
| Boxed warning | No | No |
| Pharmacy cost (NADAC) | $0.380 per tablet 200 mg tablet | $0.147 per tablet 1 mg tablet |
| Shortage now | No current entry | A presentation being discontinued |
Source: FDA NDC Directory, CMS NADAC of October 7, 2026 and the FDA Drug Shortage Database (FDA files October 8, 2026)
What next?
- Check more medicines together
- up to five at once