What the FDA labels say about taking them together
Fluoxetine and insulin lispro
Insulin lispro's FDA label of June 4, 2025 names fluoxetine in its drug interactions section; fluoxetine's label does not name insulin lispro itself but warns about its class (insulin analogs). The insulin lispro label: “Drugs That May Increase the Risk of Hypoglycemia Drugs: Antidiabetic agents, ACE inhibitors, angiotensin II receptor blocking agents, disopyramide, fibrates, fluoxetine, monoamine oxidase inhibitors, pentoxifylline …”
Check it at the source: the fluoxetine FDA label on DailyMed (effective January 8, 2026, Dista Products Company); the insulin lispro FDA label on DailyMed (effective June 4, 2025, Sanofi-Aventis U.S. LLC).
What does the fluoxetine label say about insulin lispro?
Fluoxetine's label does not name insulin lispro itself; it warns about its class (insulin analogs):
Fluoxetine label, warnings and precautionsAs is true with many other types of medication when taken concurrently by patients with diabetes, insulin and/or oral hypoglycemic, dosage may need to be adjusted when therapy with PROZAC is instituted or discontinued.
Source: FDA drug label (Prozac), NDA018936 (Eli Lilly And Co), as published by Dista Products Company, effective January 8, 2026 (SPL set c88f33ed-6dfb-4c5e-bc01-d8e36dd97299), via openFDA; the full label on DailyMed
What does the insulin lispro label say about fluoxetine?
Insulin lispro label, drug interactionsDrugs That May Increase the Risk of Hypoglycemia Drugs: Antidiabetic agents, ACE inhibitors, angiotensin II receptor blocking agents, disopyramide, fibrates, fluoxetine, monoamine oxidase inhibitors, pentoxifylline, pramlintide, salicylates, somatostatin analogs (e.g., octreotide), and sulfonamide antibiotics. Intervention: Dose adjustment and increased frequency of glucose monitoring may be required when ADMELOG is concomitantly administered with these drugs.
Source: FDA drug label (Insulin Lispro, BLA020563), Eli Lilly and Company, effective June 17, 2025 (SPL set 97d5e596-aae1-42c9-ae89-c3780959c467), via openFDA
Source: FDA drug label (ADMELOG), Sanofi-Aventis U.S. LLC, effective June 4, 2025 (SPL set 0691def8-4a7b-4de3-866f-a280989f47f1), 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
| Fluoxetine | Insulin lispro | |
|---|---|---|
| Labeled for | Depression, Anxiety, Bipolar disorder | Type 2 diabetes, Type 1 diabetes |
| Boxed warning | Yes | No |
| Pharmacy cost (NADAC) | $0.0519 per capsule 40 mg capsule | $10.19 per mL 100 unit/mL kwikpen |
| 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