The short answer
High-dose nicotinic acid can worsen glucose control during glipizide treatment. This calls for monitoring when it is started or stopped, not automatic extra niacin or a new dosing interval.
What this answer covers
Niacin forms distinguished: label interaction concerns nicotinic acid, especially pharmacologic use; ordinary food intake and nicotinamide are not interchangeable.
- Supplement or preparation
- Niacin
- Medication ingredient
- glipizide
Glipizide labels name nicotinic acid
Both inspected formulations warn that nicotinic acid can reduce glucose control. They advise observation for higher glucose during use and low glucose when an interacting medicine is withdrawn.
A large trial supports the glucose concern
High-dose extended-release niacin combined with laropiprant increased serious disturbances in diabetes control in a large vascular-risk trial. Because it was a combination product, it does not provide a glipizide-specific risk or describe ordinary nutritional intake.
This does not establish increased niacin need
A drug interaction is not evidence that glipizide depletes vitamin B3. The form and amount should be checked, particularly when a product is sold for cholesterol management rather than routine nutrition.
Plan changes with the prescriber
Discuss starting, stopping or changing high-dose nicotinic acid with the diabetes team. Glucose monitoring may need to change, but no protective spacing interval is established. Do not change glipizide or prescribed niacin on your own.
Evidence and practical considerations
Timing & monitoring
No altered nutritional requirement or timing demonstrated; narrower label-supported monitoring concern for pharmacologic nicotinic acid is distinct.
- Exact scope
- Niacin forms distinguished: label interaction concerns nicotinic acid, especially pharmacologic use; ordinary food intake and nicotinamide are not interchangeable. with Oral glipizide RxCUI4821 IN, immediate and extended release distinguished.
- Medication form and route
- oral medication; oral supplement
What remains uncertain
- Exact source preparation, medication and endpoint limits apply; no universal dose change or spacing.
Factors that may matter: Formulation; Dose and duration; Meal pattern; Other glucose-lowering agents; Kidney and liver function.
Read the supporting source summaries
Source 1: current product label
dailymed.nlm.nih.gov · Source check Sep 10, 2026
Population: Patients with type 2 diabetes receiving glipizide.
Glipizide can cause severe hypoglycemia; added glucose-lowering agents warrant observation. Nicotinic acid can worsen glycemic control; withdrawal also needs observation.
How this applies: Exact glipizide formulation and supplement preparation matter; other sulfonylureas and glucose efficacy endpoints are not automatically glipizide hypoglycemia evidence.
Separate formulations and meal instructions; no automatic transfer of immediate-release antacid pharmacokinetics to XL. Does not establish a risk rate for these herbs.
Source 2: current product label
dailymed.nlm.nih.gov · Source check Sep 10, 2026
Population: Patients with type 2 diabetes receiving glipizide.
Glipizide can cause severe hypoglycemia; added glucose-lowering agents warrant observation. Nicotinic acid can worsen glycemic control; withdrawal also needs observation.
How this applies: Exact glipizide formulation and supplement preparation matter; other sulfonylureas and glucose efficacy endpoints are not automatically glipizide hypoglycemia evidence.
Separate formulations and meal instructions; no automatic transfer of immediate-release antacid pharmacokinetics to XL. Does not establish a risk rate for these herbs.
Source 3: original human study
pubmed.ncbi.nlm.nih.gov · Source check Sep 10, 2026
Population: 25,673high-vascular-risk adults.
High-dose niacin-laropiprant increased serious disturbances in diabetes control compared with placebo.
How this applies: Exact glipizide formulation and supplement preparation matter; other sulfonylureas and glucose efficacy endpoints are not automatically glipizide hypoglycemia evidence.
Combination product, not ordinary nutritional niacin or a glipizide-specific estimate; no supplement need or protective spacing demonstrated.
Research assessment: · Open full citations ↗
Review and change history
- Publication status
- Published research summary
- Clinical review
- Not yet recorded
| Date | Update |
|---|---|
| Article prepared | |
| Prepared exact glipizide article preserving formulation, preparation and glucose endpoint distinctions. | |
| Research summary published |
Article revision: ea20511b52e7bfe0
This guide brings together the evidence records used by our interaction checker. Each finding retains its own preparation limits, research date, and source summaries.
Full citations require verification. Reading this answer and the source summaries does not.
Taking other supplements or medications?
Use the checker to explore your other combinations. Ask a pharmacist to review the exact products, amounts and medical conditions in your complete list.
Open the interaction checkerInformation, not medical advice. Do not change prescribed treatment based on this guide.