What the FDA labels say about taking them together
Leucovorin and levoleucovorin
Leucovorin's FDA label (Vykoura) of March 12, 2026 names levoleucovorin in its contraindications section, and levoleucovorin's label names leucovorin too. The levoleucovorin label: “Toxicities with Fluorouracil Leucovorin products increase the toxicities of fluorouracil.”
Check it at the source: the leucovorin FDA label on DailyMed (effective March 19, 2025, Meitheal Pharmaceuticals Inc.); the levoleucovorin FDA label on DailyMed (effective August 29, 2023, Slate Run Pharmaceuticals).
What does the leucovorin label say about levoleucovorin?
Vykoura label (Avyxa Pharma, LLC, March 12, 2026), contraindicationsCONTRAINDICATIONS VYKOURA is contraindicated in patients who have had a severe hypersensitivity reaction to leucovorin (folinic acid), levoleucovorin, or folic acid [see Warnings and Precautions (5.1) ].
Source: FDA drug label (Vykoura, NDA220406), Avyxa Pharma, LLC, effective March 12, 2026 (SPL set d122b875-435e-4e00-b945-7a0546df95c2), via openFDA
Source: FDA drug label (leucovorin calcium), Meitheal Pharmaceuticals Inc., effective March 19, 2025 (SPL set 9df20901-6980-4d4e-89ec-40f3c1f91852), via openFDA; the full label on DailyMed
What does the levoleucovorin label say about leucovorin?
Levoleucovorin label, contraindicationsCONTRAINDICATIONS Levoleucovorin is contraindicated in patients who have had severe hypersensitivity to leucovorin products, folic acid or folinic acid [see Adverse Reactions ( 6.2 )].
Levoleucovorin label, drug interactionsDRUG INTERACTIONS 7.1 Effects of Leucovorin Products on Other Drugs Antiepileptic Drugs Folic acid in large amounts may counteract the antiepileptic effect of phenobarbital, phenytoin and primidone and increase the frequency of seizures in susceptible children.
Levoleucovorin label, warnings and precautionsIncreased rates of treatment failure and morbidity with concomitant use of d, l- leucovorin with trimethoprim-sulfamethoxazole for Pneumocystis jiroveci pneumonia in patients with HIV.
Khapzory label (Acrotech Biopharma Inc, March 17, 2026), warnings and precautionsToxicities with Fluorouracil Leucovorin products increase the toxicities of fluorouracil [see Drug Interactions ( 7 )].
Source: FDA drug label (Khapzory, NDA211226), Acrotech Biopharma Inc, effective March 17, 2026 (SPL set 344f65ac-9f04-49d7-b7c3-4ba19bd7b429), via openFDA
Source: FDA drug label (LEVOLEUCOVORIN CALCIUM), Slate Run Pharmaceuticals, effective August 29, 2023 (SPL set 124bc214-62f8-40f9-a227-a35e2d1ff2a0), 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
| Leucovorin | Levoleucovorin | |
|---|---|---|
| Labeled for | Colorectal cancer | Colorectal cancer |
| Boxed warning | No | No |
| Pharmacy cost (NADAC) | $0.330 per tablet 5 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