What the FDA labels say about taking them together
Clarithromycin and ivacaftor
Ivacaftor's FDA label of March 23, 2026 names clarithromycin in its drug interactions section; the clarithromycin label PlainMeds reads does not name ivacaftor. The ivacaftor label: “… ketoconazole, itraconazole, posaconazole, voriconazole, telithromycin, and clarithromycin.”
Check it at the source: the clarithromycin FDA label on DailyMed (effective April 9, 2026, Solaris Pharma Corporation); the ivacaftor FDA label on DailyMed (effective March 23, 2026, Vertex Pharmaceuticals Incorporated).
What does the clarithromycin label say about ivacaftor?
Clarithromycin's label (effective April 9, 2026) does not name ivacaftor in these sections. A label lists what its studies and reports found; it is not a complete list.
Source: FDA drug label (Clarithromycin), Solaris Pharma Corporation, effective April 9, 2026 (SPL set 4d42821d-ce7a-7d64-e063-6294a90a0875), via openFDA; the full label on DailyMed
What does the ivacaftor label say about clarithromycin?
Ivacaftor label, drug interactionsBased on simulations of these results, a reduction of the KALYDECO dosage is recommended for patients aged 6 months and older taking concomitant strong CYP3A inhibitors, such as ketoconazole, itraconazole, posaconazole, voriconazole, telithromycin, and clarithromycin.
Source: FDA drug label (Kalydeco), Vertex Pharmaceuticals Incorporated, effective March 23, 2026 (SPL set 0ab0c9f8-3eee-4e0f-9f3f-c1e16aaffe25), 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
| Clarithromycin | Ivacaftor | |
|---|---|---|
| Labeled for | Bacterial infections, Acid reflux and ulcers | n/a |
| Boxed warning | No | No |
| Pharmacy cost (NADAC) | $0.466 per tablet 500 mg tablet | n/a |
| 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