What the FDA labels say about taking them together
Dofetilide and trilaciclib
Trilaciclib's FDA label of August 31, 2025 names dofetilide in its drug interactions section; the dofetilide label PlainMeds reads does not name trilaciclib. The trilaciclib label: “The potential benefits of taking COSELA concurrently with dofetilide should be considered against the risk of QT interval prolongation.; …”
Check it at the source: the dofetilide FDA label on DailyMed (effective April 21, 2026, Pfizer Laboratories Div Pfizer Inc); the trilaciclib FDA label on DailyMed (effective August 31, 2025, Pharmacosmos Therapeutics Inc.).
What does the dofetilide label say about trilaciclib?
Dofetilide's label (effective April 21, 2026) does not name trilaciclib in these sections. A label lists what its studies and reports found; it is not a complete list.
Source: FDA drug label (Tikosyn), Pfizer Laboratories Div Pfizer Inc, effective April 21, 2026 (SPL set 02438044-d6a3-49e9-a1ac-3aad21ef2c8c), via openFDA; the full label on DailyMed
What does the trilaciclib label say about dofetilide?
Trilaciclib label, drug interactionsDrugs: Dofetilide; Recommendations: The potential benefits of taking COSELA concurrently with dofetilide should be considered against the risk of QT interval prolongation.; Comments: Increased dofetilide blood levels may occur in patients who are also receiving COSELA. Increased plasma concentrations of dofetilide may cause serious ventricular arrhythmias associated with QT interval prolongation, including torsade de pointes.
Source: FDA drug label (COSELA), Pharmacosmos Therapeutics Inc., effective August 31, 2025 (SPL set b3179c19-78f3-4bf1-b73e-7f7638522ab1), 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
| Dofetilide | Trilaciclib | |
|---|---|---|
| Labeled for | Atrial fibrillation | n/a |
| Boxed warning | Yes | No |
| Pharmacy cost (NADAC) | $0.203 per capsule 125 mcg capsule | 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