What the FDA labels say about taking them together
Abatacept and acyclovir
Abatacept's FDA label of November 13, 2025 names acyclovir in its warnings and precautions section; the acyclovir labels PlainMeds reads (4) do not name abatacept.
Check it at the source: the abatacept FDA label on DailyMed (effective November 13, 2025, E.R. Squibb & Sons, L.L.C.); the acyclovir FDA label on DailyMed (effective July 24, 2026, Heritage Pharmaceuticals Inc. d/b/a Avet Pharmaceuticals Inc.).
What does the abatacept label say about acyclovir?
Abatacept label, warnings and precautionsThree of the 4 patients discontinued acyclovir prophylaxis at day 30 post-transplant.
Source: FDA drug label (ORENCIA), E.R. Squibb & Sons, L.L.C., effective November 13, 2025 (SPL set 0836c6ac-ee37-5640-2fed-a3185a0b16eb), via openFDA; the full label on DailyMed
What does the acyclovir label say about abatacept?
Acyclovir's label (effective July 24, 2026) and its 3 other brand-application labels do not name abatacept in these sections. A label lists what its studies and reports found; it is not a complete list.
Source: FDA drug label (ACYCLOVIR), Heritage Pharmaceuticals Inc. d/b/a Avet Pharmaceuticals Inc., effective July 24, 2026 (SPL set 0de2f5c7-9e75-4bdf-9c28-e026cc6694b4), 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
| Abatacept | Acyclovir | |
|---|---|---|
| Labeled for | Rheumatoid arthritis | Herpes and shingles |
| Boxed warning | No | No |
| Pharmacy cost (NADAC) | $1,469.23 per mL 125 mg/mL syringe | $0.0962 per tablet 400 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