What the FDA labels say about taking them together
Sarilumab and theophylline
Sarilumab's FDA label of February 27, 2026 names theophylline in its drug interactions section; the theophylline label PlainMeds reads does not name sarilumab. The sarilumab label: “… therapeutic monitoring of effect (e.g., warfarin) or drug concentration (e.g., theophylline) and adjust the individual dose of the medicinal product as needed.”
Check it at the source: the sarilumab FDA label on DailyMed (effective February 27, 2026, Sanofi-Aventis U.S. LLC); the theophylline FDA label on DailyMed (effective March 10, 2026, Strides Pharma Science Limited).
What does the sarilumab label say about theophylline?
Sarilumab label, drug interactionsUpon initiation or discontinuation of KEVZARA, in patients being treated with CYP substrate medicinal products, perform therapeutic monitoring of effect (e.g., warfarin) or drug concentration (e.g., theophylline) and adjust the individual dose of the medicinal product as needed.
Source: FDA drug label (KEVZARA), Sanofi-Aventis U.S. LLC, effective February 27, 2026 (SPL set 827bc01c-d379-4266-a18c-c7f904b76af3), via openFDA; the full label on DailyMed
What does the theophylline label say about sarilumab?
Theophylline's label (effective March 10, 2026) does not name sarilumab in these sections. A label lists what its studies and reports found; it is not a complete list.
Source: FDA drug label (Theophylline), Strides Pharma Science Limited, effective March 10, 2026 (SPL set b7a90ccf-9c32-40cc-9008-7e55b3da4dfd), 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
| Sarilumab | Theophylline | |
|---|---|---|
| Labeled for | Rheumatoid arthritis | Asthma |
| Boxed warning | Yes | No |
| Pharmacy cost (NADAC) | $2,075.30 per mL 200 mg/1.14 mL pen injection | $0.330 per tablet 300 mg tablet |
| Shortage now | No current entry | No current entry |
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