What the FDA labels say about taking them together
Clarithromycin and nirmatrelvir/ritonavir
Nirmatrelvir/ritonavir's FDA label of February 19, 2026 names clarithromycin in its drug interactions section; the clarithromycin label PlainMeds reads does not name nirmatrelvir/ritonavir. The nirmatrelvir/ritonavir label: “Refer to the respective prescribing information for anti-infective dose adjustment.”
Check it at the source: the clarithromycin FDA label on DailyMed (effective April 9, 2026, Solaris Pharma Corporation); the nirmatrelvir/ritonavir FDA label on DailyMed (effective February 19, 2026, Pfizer Laboratories Div Pfizer Inc).
What does the clarithromycin label say about nirmatrelvir/ritonavir?
Clarithromycin's label (effective April 9, 2026) does not name nirmatrelvir/ritonavir 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 nirmatrelvir/ritonavir label say about clarithromycin?
Nirmatrelvir/ritonavir label, drug interactionsDrug Class: Anti-infective; Drugs within Class: clarithromycin, erythromycin; Effect on Concentration: ↑ clarithromycin ↑ erythromycin; Clinical Comments: Refer to the respective prescribing information for anti-infective dose adjustment.
Source: FDA drug label (Paxlovid), Pfizer Laboratories Div Pfizer Inc, effective February 19, 2026 (SPL set 8a99d6d6-fd9e-45bb-b1bf-48c7f761232a), 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 | Nirmatrelvir/ritonavir | |
|---|---|---|
| Labeled for | Bacterial infections, Acid reflux and ulcers | COVID-19 |
| Boxed warning | No | Yes |
| Pharmacy cost (NADAC) | $0.466 per tablet 500 mg tablet | $49.24 per unit 300-100 mg dose pack |
| 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