What the FDA labels say about taking them together
Ritonavir and theophylline
Ritonavir's FDA label of July 23, 2026 names theophylline in its drug interactions section; the theophylline label PlainMeds reads does not name ritonavir. The ritonavir label: “Increased dosage of theophylline may be required; therapeutic monitoring should be considered.”
Check it at the source: the ritonavir FDA label on DailyMed (effective July 23, 2026, AbbVie Inc.); the theophylline FDA label on DailyMed (effective March 10, 2026, Strides Pharma Science Limited).
What does the ritonavir label say about theophylline?
Ritonavir label, drug interactionsConcomitant Drug Class/Drug Name: Bronchodilator: theophylline; Effect on Concentration of Ritonavir or Concomitant Drug: ↓ theophylline; Clinical Comment: Increased dosage of theophylline may be required; therapeutic monitoring should be considered.
Source: FDA drug label (Norvir), AbbVie Inc., effective July 23, 2026 (SPL set 2849298e-de6e-47bb-8194-56e075b33fc3), via openFDA; the full label on DailyMed
What does the theophylline label say about ritonavir?
Theophylline's label (effective March 10, 2026) does not name ritonavir 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
| Ritonavir | Theophylline | |
|---|---|---|
| Labeled for | HIV | Asthma |
| Boxed warning | Yes | No |
| Pharmacy cost (NADAC) | $0.607 per tablet 100 mg tablet | $0.330 per tablet 300 mg tablet |
| Shortage now | A presentation being discontinued | 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