What the FDA labels say about taking them together
Cilastatin/imipenem and divalproex
Cilastatin/imipenem's FDA label of July 5, 2024 names divalproex in its drug interactions section; the divalproex labels PlainMeds reads (3) do not name cilastatin/imipenem. The cilastatin/imipenem label: “Valproic acid/divalproex sodium: Concomitant use with PRIMAXIN is generally not recommended.”
Check it at the source: the cilastatin/imipenem FDA label on DailyMed (effective July 5, 2024, Merck Sharp & Dohme LLC); the divalproex FDA label on DailyMed (effective March 31, 2026, AbbVie Inc.).
What does the cilastatin/imipenem label say about divalproex?
Cilastatin/imipenem label, drug interactionsValproic acid/divalproex sodium: Concomitant use with PRIMAXIN is generally not recommended.
Cilastatin/imipenem label, warnings and precautionsIncreased Seizure Potential Due to Interaction with Valproic Acid: Co-administration of PRIMAXIN, to patients receiving valproic acid or divalproex sodium results in a reduction in valproic acid concentrations.
Source: FDA drug label (PRIMAXIN IV), Merck Sharp & Dohme LLC, effective July 5, 2024 (SPL set f41d8abd-7792-4918-1b93-bd83ea01955e), via openFDA; the full label on DailyMed
What does the divalproex label say about cilastatin/imipenem?
Divalproex's label (effective March 31, 2026) and its 2 other brand-application labels do not name cilastatin/imipenem in these sections. A label lists what its studies and reports found; it is not a complete list.
Source: FDA drug label (Depakote), AbbVie Inc., effective March 31, 2026 (SPL set 08a65cf4-7749-4ceb-6895-8f4805e2b01f), 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
| Cilastatin/imipenem | Divalproex | |
|---|---|---|
| Labeled for | Bacterial infections, Urinary tract infections | Bipolar disorder, Migraine, Seizures and epilepsy |
| Boxed warning | No | Yes |
| Pharmacy cost (NADAC) | n/a | $0.194 per tablet 500 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