What the FDA labels say about taking them together
Cobicistat and dexamethasone
Cobicistat's FDA label of February 10, 2026 names dexamethasone in its drug interactions section; the dexamethasone labels PlainMeds reads (4) do not name cobicistat. The cobicistat label: “Coadministration with oral dexamethasone or other systemic corticosteroids that induce CYP3A may result in loss of therapeutic effect and development of resistance to atazanavir or darunavir. …”
Check it at the source: the cobicistat FDA label on DailyMed (effective February 10, 2026, Gilead Sciences, Inc.); the dexamethasone FDA label on DailyMed (effective June 6, 2025, Hikma Pharmaceuticals USA, Inc.).
What does the cobicistat label say about dexamethasone?
Cobicistat label, drug interactionsConcomitant Drug Class/Drug Name: Corticosteroids: e.g., betamethasone budesonide ciclesonide dexamethasone fluticasone methylprednisolone mometasone triamcinolone; Potential Effect ↑ = Increase, ↓ = Decrease, ↔ = No change: ↓ cobicistat ↓ atazanavir ↓ darunavir ↑ corticosteroids; Clinical Comment: Coadministration with oral dexamethasone or other systemic corticosteroids that induce CYP3A may result in loss of therapeutic effect and development of resistance to atazanavir or darunavir. Consider alternative corticosteroids. …
Source: FDA drug label (Tybost), Gilead Sciences, Inc., effective February 10, 2026 (SPL set 3784c35c-e87f-410c-900b-8fd6313c6010), via openFDA; the full label on DailyMed
What does the dexamethasone label say about cobicistat?
Dexamethasone's label (effective June 6, 2025) and its 3 other brand-application labels do not name cobicistat in these sections. A label lists what its studies and reports found; it is not a complete list.
Source: FDA drug label (Dexamethasone Intensol), Hikma Pharmaceuticals USA, Inc., effective June 6, 2025 (SPL set b15200fb-1826-472b-a907-e677a272513b), 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
| Cobicistat | Dexamethasone | |
|---|---|---|
| Labeled for | HIV | Asthma, Eczema (atopic dermatitis), Leukemia, lymphoma and myeloma, Herpes and shingles, Crohn's disease and ulcerative colitis, Multiple sclerosis, Osteoarthritis, Rheumatoid arthritis, Psoriasis, Allergies, Anemia, Pain |
| Boxed warning | No | No |
| Pharmacy cost (NADAC) | n/a | $0.193 per tablet 4 mg tablet |
| Shortage now | A presentation being discontinued | In shortage |
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