Acarbose and Chlorpropamide: Interaction Details
AI-assisted, pharmacist-reviewed · AI content regenerated Jul 11, 2026 · Source data updated Jul 10, 2026 · Sources: FDA labeling, DDInter 2.0, cited literature
Chlorpropamide
Acarbose
How we grade severity & evidence
Severity levels
- Contraindicated: These should generally not be used together.
- Major: Potentially serious — often needs a change or close monitoring.
- Moderate: Can be significant — usually manageable with monitoring.
- Minor: Usually limited clinical impact.
Evidence grades
- Established: Well documented — supported by controlled studies or strong clinical data.
- Probable: Good supporting evidence, though not definitively proven.
- Suspected: Some evidence suggests this interaction, but it is not well established.
- Possible: Limited or conflicting evidence; the interaction may occur.
- Theoretical: Predicted from the drugs' pharmacology; not yet confirmed in people.
Ratings come from the documented interaction literature and are reviewed by a pharmacist. They describe the documented risk of the combination, not what will necessarily happen to you — your dose, timing, and health picture all matter.
Both of these medicines lower your blood sugar, just in different ways. Chlorpropamide (Diabinese) tells your body to release more insulin, while acarbose (Precose) slows how fast you absorb carbs from meals. When you take them together, their sugar-lowering effects add up, so your blood sugar can drop too low. That is called hypoglycemia, and it can make you shaky, sweaty, confused, or dizzy.
Here is an important tip: if your sugar drops, use glucose tablets or glucose gel, not table sugar or candy. Acarbose blocks the breakdown of regular sugar, so it will not fix a low fast enough. Your care team can manage this easily by checking your sugars and adjusting your doses.
Effect: Additive hypoglycemic effect increasing risk of hypoglycemia when acarbose is combined with the sulfonylurea chlorpropamide.
- Mechanism: Pharmacodynamic (additive). Chlorpropamide is an insulin secretagogue; acarbose is an alpha-glucosidase inhibitor delaying carbohydrate absorption. Neither is a prodrug relevant here.
- Onset: Rapid. Evidence: Theoretical.
- Severity: Major given chlorpropamide's long half-life and prolonged hypoglycemia risk.
- Management: Monitor blood glucose closely when acarbose is started or stopped; individualize/adjust doses. Treat hypoglycemia with oral glucose (dextrose), NOT sucrose, since acarbose inhibits sucrose hydrolysis.
What happens
An increased risk of hypoglycemia
Interaction Deep Dive
When acarbose is given together with a sulfonylurea drug, blood glucose falls, which heightens the hypoglycemic potential of the sulfonylurea1. Acarbose on its own neither raises insulin availability nor enhances its activity. The way it lowers hyperglycemia is by slowing or blocking the uptake of carbohydrates from the intestine, so blood glucose climbs less sharply after eating. Individuals taking acarbose along with a sulfonylurea must be alerted to their elevated hypoglycemia risk and should be ready to handle such an event.
Why it happens (mechanism)
Additive hypoglycemic effects
How to manage this interaction
Keep taking both medicines as prescribed unless your prescriber tells you otherwise. This combination is manageable with a few simple steps.
- Your care team may check your blood sugar more closely, especially when acarbose is being added or stopped.
- The dose of either or both drugs may need to be adjusted and individualized by your care team to reduce lows.
- Carry glucose tablets or glucose liquid to treat a low. Do not rely on table sugar, candy, or juice, because acarbose blocks the breakdown of regular sugar and it will not work fast enough.
- Tell your pharmacist or doctor about any shakiness, sweating, or confusion.
Management is individual — confirm any change with your pharmacist or prescriber.
Common questions
Can I take Acarbose and Chlorpropamide together?
Taking chlorpropamide and acarbose together can add up to cause low blood sugar, so monitor your levels and always carry glucose tablets (not table sugar) to treat a low fast. Always confirm with your pharmacist or prescriber before making any change.
How serious is the Acarbose and Chlorpropamide interaction?
It is rated major. Potentially serious — often needs a change or close monitoring.
How quickly could this interaction happen?
The documented onset is "rapid". Effects can appear quickly, often within about 24 hours of combining the drugs.
How is the Acarbose and Chlorpropamide interaction managed?
Keep taking both medicines as prescribed unless your prescriber tells you otherwise. This combination is manageable with a few simple steps. Your care team may check your blood sugar more closely, especially when acarbose is being added or stopped. The dose of either or both drugs may need to be adjusted and individualized by your care team to reduce lows. Carry glucose tablets or glucose liquid t… Management is individual — always follow your own care team's guidance.
How strong is the evidence for this interaction?
The evidence is graded "theoretical". Predicted from the drugs' pharmacology; not yet confirmed in people.
Questions for your pharmacist
- Does my dose of Acarbose or Chlorpropamide need adjusting while I take them together?
- What symptoms should prompt me to call you or my prescriber right away?
- Does the timing of my doses matter for this combination?
- Is there a safer alternative to one of these medications for me?
References (1)
- Product Information: Precose(R), acarbose. Bayer Corporation, West Haven, CT, 1998. DailyMed
Keep reading about Chlorpropamide
Keep reading about Acarbose
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