Guide
Blood Sugar Supplements With Metformin, Insulin and Sulfonylureas
Blood sugar supplements with metformin, insulin or a sulfonylurea need a talk with your doctor or pharmacist first. The ADA warns that some supplements can cause low blood sugar when combined with diabetes medicines. Chromium, an ingredient in Glyco Defender, may add to insulin and other diabetes drugs. Learn the signs of a low, and never stop a prescribed medicine to make room for a supplement.
Written by the Glyco Defender label deskUpdated
The short answer01
Can you take supplements with diabetes medicines?
You can take some supplements with diabetes medicines, but only after your care team has checked them. The ADA advises discussing any supplement with your healthcare team first (ADA, Vitamins & Supplements).
The main worry is a low. The ADA says some supplements can cause low blood glucose when they are combined with diabetes medications.
"Natural" is not a safety stamp. NCCIH points out that supplements can interact with prescription and over-the-counter medicines, and that some products have held ingredients not on the label (NCCIH, Using Dietary Supplements Wisely).
FDA gives the same advice in plain terms: talk to a doctor, pharmacist or other health professional before you use a supplement (FDA, Using Dietary Supplements).
Metformin02
Is it safe to take blood sugar supplements with metformin?
Taking blood sugar supplements with metformin is a question for your prescriber, because herbs can stack on top of the drug's effect.
One example comes from the Glyco Defender label itself. Astragalus is sixth in the blend. A 2024 review of 20 mostly low-quality studies found astragalus plus metformin lowered fasting glucose and A1C more than metformin alone (NCCIH, Astragalus).
An added effect is exactly what your doctor needs to know about, because it changes how your numbers read.
Metformin is a well-tested drug. In the Diabetes Prevention Program it cut the risk of type 2 diabetes by 31% (NIDDK, Diabetes Prevention Program). No trial has tested Glyco Defender with it or alone.
Insulin and sulfonylureas03
What happens if you combine supplements with insulin or a sulfonylurea?
Combining supplements with insulin or a sulfonylurea raises the chance of a low, because these drugs can cause lows on their own (NIDDK, Low Blood Glucose).
NIDDK names insulin, sulfonylureas and meglitinides as medicines that can cause low blood glucose. A supplement that nudges glucose down adds to that push.
Several Glyco Defender lines carry this caution. Chromium may strengthen the effect of insulin and other diabetes drugs (NIH ODS, Chromium). Asian ginseng might lower blood sugar (NCCIH, Asian Ginseng). MSK lists use of African mango with diabetes drugs as a caution (MSKCC, Irvingia gabonensis (African mango)). Gymnema may also add to diabetes medicines.
The doses in one dropperful are small: 7 mcg of chromium and a 15.47 mg blend shared by 21 lines. Small is not the same as zero, so the check with your doctor still applies.
Low blood sugar04
What are the signs of low blood sugar?
The signs of low blood sugar include shakiness, hunger, tiredness, dizziness, confusion, irritability and a fast or uneven heartbeat (NIDDK, Low Blood Glucose).
Many people with diabetes count a reading under 70 mg/dL as a low. Severe lows can lead to seizures or passing out.
If you add any supplement while on insulin or a sulfonylurea, learn these signs and keep fast carbohydrate on hand. The steps below come from NIDDK.
- Shaky or jitteryTrembling hands, feeling nervous
- Tired or irritableSudden tiredness or a short temper
- Hungry, nauseousSudden strong hunger
- Dizzy, confusedTrouble thinking or speaking clearly
- Fast heartbeatPounding or racing pulse
15-15For many people with diabetes, a low is under 70 mg/dL. Take 15-20 g of fast carbohydrate (juice, glucose tablets), then check again in 15 minutes.
Call 911When someone with a low passes out, has a seizure or cannot safely swallow. Do not give food or drink to someone who is unconscious.
Signs and steps from NIDDK (NIDDK, Low Blood Glucose). Insulin, sulfonylureas and meglitinides can cause lows; supplements may add to them (ADA, Vitamins & Supplements).
Other medicines05
Which Glyco Defender ingredients interact with other medicines?
Glyco Defender ingredients with known medicine interactions include chromium, green tea, grapefruit seed, licorice compound, L-tryptophan, eleuthero, guarana and forskolin.
The table covers more than glucose drugs, since thyroid, heart and mood medicines often share the list.
Each row is what the cited source says about the ingredient in general. None of these sources tested Glyco Defender. The amounts in one dropperful are not printed for blend lines.
| Label line | Medicine type | What the source says |
|---|---|---|
| Chromium | Insulin, diabetes drugs, levothyroxine | May add to diabetes drugs; may reduce levothyroxine absorption (NIH ODS, Chromium) |
| Green tea | Nadolol (a beta-blocker) | High doses lower nadolol blood levels (NCCIH, Green Tea) |
| Grapefruit seed | Some statins, blood-pressure and heart-rhythm drugs | Grapefruit juice blocks an enzyme that clears some drugs (FDA, Grapefruit juice and drugs) |
| Monoammonium glycyrrhizinate | Corticosteroids; blood pressure | Licorice interactions with corticosteroids reported (NCCIH, Licorice Root) |
| L-tryptophan | MAO inhibitors, tramadol, other serotonin drugs | Not without medical advice (Drugs.com, L-tryptophan) |
| Eleuthero | Digoxin | Raised digoxin levels in a case report (MSKCC, Siberian Ginseng (Eleuthero)) |
| Guarana, forskolin | Warfarin and other blood thinners | May raise bleeding risk (MSKCC, Guarana) (MSKCC, Forskolin (Coleus forskohlii)) |
The full safety list sits on our Glyco Defender side effects page.
Glyco Defender: from $49 a bottle30 mL · 1, 3 or 6 bottles · free US shipping on 6 · 60-day money-back guarantee
See packsPharmacist06
How do you talk to a pharmacist about a supplement?
To talk to a pharmacist about a supplement, bring the bottle or a clear photo of its Supplement Facts panel, plus a list of every medicine you take.
FDA's grapefruit guidance makes the same point: ask a doctor or pharmacist whether your medicine is affected (FDA, Grapefruit juice and drugs).
Be specific. A pharmacist can only judge what they can see, so show the whole ingredient list, not just the brand name.
Show the label
Point out the 7 mcg of chromium and the 21 blend lines, from maca to L-carnitine.
List your medicines
Include doses and times, plus any other supplement or over-the-counter product.
Ask about lows
Ask whether the mix could push you under 70 mg/dL, and how often to check your meter.
Tell every provider
NCCIH advises telling all your providers about supplements, especially before surgery (NCCIH, Using Dietary Supplements Wisely).
Your prescription07
Should you stop diabetes medicine to try a supplement?
No. You should not stop diabetes medicine to try a supplement. NCCIH says it is very important not to replace medical treatment for diabetes with an unproven product (NCCIH, Diabetes and Dietary Supplements).
FDA has warned companies that illegally sell products, including supplements, with claims to treat diabetes. It states it has not approved those products as safe and effective (FDA, Illegally Sold Diabetes Treatments).
Take your diabetes medicine exactly as prescribed, whatever supplement you use. Any change to a dose is a decision for you and your prescriber, made together.
Glyco Defender is a dietary supplement, not a medicine. Our who Glyco Defender is for page has a short fit check.
Tracking08
What should you track after adding a supplement to diabetes medicine?
After adding a supplement to diabetes medicine, track your meter readings, any low symptoms and the day you started, then share the log with your care team.
A start date matters. Without it, nobody can tell whether a change in your numbers came from the supplement, a meal or something else.
With Glyco Defender, one bottle holds 30 servings at one dropperful a day, so a bottle is a natural point to review. Compare your log with the ranges on our blood sugar numbers guide.
- Start date and time of day you take the drops
- Meter readings, with notes on meals
- Any shaky, dizzy or confused spells
- Any change your doctor makes to a medicine
FAQ09
Supplements and diabetes medicine questions
Can blood sugar supplements cause low blood sugar with diabetes medicine?
Yes, they can. The ADA warns that some supplements can cause low blood glucose when combined with diabetes medications. The risk is highest with insulin, sulfonylureas and meglitinides, which NIDDK says can cause lows on their own. Ask your doctor before adding any supplement, and learn the signs of a low.
Can I take chromium with metformin?
Ask your prescriber first. The NIH says chromium may add to the effect of insulin and other diabetes drugs. Chromium-only supplements often hold 200 to 500 mcg; Glyco Defender lists 7 mcg per dropperful. Even small amounts are worth mentioning so your doctor can read your numbers correctly.
Which supplements should people on insulin avoid?
There is no single list, so ask your care team about each product. Ingredients flagged with diabetes drugs include chromium, Asian ginseng, African mango and gymnema. All four appear on the Glyco Defender label. Insulin can cause lows by itself, so any added glucose effect needs a plan.
What should I do if my blood sugar drops low after starting a supplement?
Treat the low first: take 15 to 20 grams of fast carbohydrate, such as juice or glucose tablets, and recheck in 15 minutes. Call 911 if the person passes out, has a seizure or cannot swallow safely. Then call your doctor before taking another dose.
Do supplements interact with thyroid medicine for people with diabetes?
Chromium may reduce the absorption of levothyroxine, a common thyroid medicine, according to the NIH. Glyco Defender lists 7 mcg of chromium per dropperful. Ask your pharmacist how to space the two, and keep your thyroid and diabetes medicines on the schedule your prescriber set.
What questions should I ask a pharmacist about supplements and diabetes medicines?
Ask whether any ingredient adds to your diabetes medicine, whether a low is more likely, how often to check your meter, and whether timing matters. Bring the Supplement Facts panel and a full medicine list, including over-the-counter products, so the pharmacist can check every line.
Can a supplement replace my diabetes medicine?
No. NCCIH says no unproven product should replace medical treatment for diabetes, and the ADA finds no supplement proven to lower blood glucose. FDA has warned sellers that claim supplements treat diabetes. Keep your prescription exactly as directed and talk to your doctor about any change.
Who wrote this10
Written and reviewed by
Pages built from the label, the sales page and linked NIH, FDA, CDC, FTC and peer-reviewed sources.
Last updated . Read our editorial standards and how we check reviews. This website is run by a licensed U.S. retail desk for Glyco Defender, not by the manufacturer or the label's distributor. Buying through our order links earns us money.
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