What the FDA labels say about taking them together
Mycophenolate mofetil and omeprazole
Omeprazole's FDA label of April 22, 2024 names mycophenolate mofetil in its drug interactions section; mycophenolate mofetil's label does not name omeprazole itself but warns about its class (Proton pump inhibitors (PPIs)). The omeprazole label: “Omeprazole can reduce the absorption of other drugs due to its effect on reducing intragastric acidity.”
Check it at the source: the mycophenolate mofetil FDA label on DailyMed (effective August 5, 2026, Genentech, Inc.); the omeprazole FDA label on DailyMed (effective April 22, 2024, Apotex Corp).
What does the mycophenolate mofetil label say about omeprazole?
Mycophenolate mofetil's label does not name omeprazole itself; it warns about its class (Proton pump inhibitors (PPIs)):
Mycophenolate mofetil label, drug interactionsDRUG INTERACTIONS See FPI for drugs that may interfere with systemic exposure and reduce CELLCEPT efficacy: antacids with magnesium or aluminum hydroxide, proton pump inhibitors, drugs that interfere with enterohepatic recirculation, telmisartan, calcium-free phosphate binders. ( 7.1 ) CELLCEPT may reduce effectiveness of oral contraceptives.
Mycophenolate mofetil label, drug interactionsProton Pump Inhibitors (PPIs) Clinical Impact Concomitant use with PPIs decreases MPA systemic exposure [see Clinical Pharmacology (12.3) ], which may reduce CELLCEPT efficacy.
Source: FDA drug label (CellCept), NDA050722 (Roche Palo), as published by Genentech, Inc., effective August 5, 2026 (SPL set 37241e87-4af4-4dc3-a1aa-ea6f20d8dc40), via openFDA; the full label on DailyMed
What does the omeprazole label say about mycophenolate mofetil?
Omeprazole label, drug interactionsClinical Impact: Omeprazole can reduce the absorption of other drugs due to its effect on reducing intragastric acidity. Intervention: Mycophenolate mofetil (MMF): Co-administration of omeprazole in healthy subjects and in transplant patients receiving MMF has been reported to reduce the exposure to the active metabolite, mycophenolic acid (MPA), possibly due to a decrease in MMF solubility at an increased gastric pH. …
Source: FDA drug label (Omeprazole), Apotex Corp, effective April 22, 2024 (SPL set b83329ac-a65e-b3af-a3fb-c5a6c740e5e7), 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
| Mycophenolate mofetil | Omeprazole | |
|---|---|---|
| Labeled for | Organ transplant rejection | Acid reflux and ulcers |
| Boxed warning | Yes | No |
| Pharmacy cost (NADAC) | $0.138 per capsule 250 mg capsule | $0.0295 per capsule 20 mg capsule |
| Shortage now | No current entry | A presentation being discontinued |
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