Safety
Glyco Defender Side Effects: Caffeine, Lows, Drug Interactions and Who Should Skip the Drops
Glyco Defender side effects have never been measured, because no trial has tested the drops. Possible effects come from the ingredients: jitters or poor sleep from the caffeine in guarana and green tea, stomach upset, and low blood sugar when taken with insulin or a sulfonylurea. The xylitol in the drops is dangerous to dogs.
Written by the Glyco Defender label deskUpdated
The short list01
What are the side effects of Glyco Defender?
The known side effects of Glyco Defender are the ones reported for its ingredients, since the product itself has no safety study. The most likely are caffeine effects and an upset stomach.
Most of those reports come from doses far larger than a dropperful. The whole blend weighs 15.47 mg per mL, shared by 21 lines, about 0.74 mg each on an even split.
Small doses lower the odds, but they do not remove them. Caffeine, interactions and xylitol matter even in small amounts.
| Possible effect | Label lines behind it | Source |
|---|---|---|
| Jitters, poor sleep, racing heart, headache | Guarana and green tea (caffeine) | (FDA, Caffeine: how much is too much?) (MSKCC, Guarana) |
| Insomnia | Panax ginseng | (NCCIH, Asian Ginseng) |
| Gas, headache, trouble sleeping | African mango | (MSKCC, Irvingia gabonensis (African mango)) |
| Stomach irritation | Cayenne pepper extract | (MSKCC, Cayenne (Capsicum)) |
| Dulled sweet taste | Gymnema | (Drugs.com, Gymnema monograph) |
| Rare liver injury | Green tea extract; one gymnema tea case | (NCCIH, Green Tea) (Drugs.com, Gymnema monograph) |
Low blood sugar02
Can Glyco Defender cause low blood sugar?
If you also use insulin, a sulfonylurea or a meglitinide, Glyco Defender could add to a low. Those medicines can bring on lows by themselves (NIDDK, Low Blood Glucose).
Chromium may strengthen the effect of insulin and other diabetes drugs (NIH ODS, Chromium). Gymnema and ginseng might lower glucose too (NCCIH, Asian Ginseng). The ADA warns that some supplements cause lows when combined with diabetes medicines (ADA, Vitamins & Supplements).
For many people with diabetes, a low is a reading under 70 mg/dL. Learn the signs below, and keep fast carbohydrate close by.
Never stop, skip or change a diabetes drug because you started the drops. Tell your doctor first, and check your meter more often for the first weeks.
- 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).
Caffeine03
Can the caffeine in Glyco Defender cause jitters or poor sleep?
Yes, in caffeine-sensitive people. Guarana and green tea both supply caffeine, and the label prints no caffeine amount (MSKCC, Guarana).
FDA cites 400 mg a day as an amount most healthy adults handle without problems (FDA, Caffeine: how much is too much?). Too much can cause a racing heartbeat, shakiness, anxiety and trouble sleeping.
Count the drops with your coffee, tea and energy drinks. A morning dose avoids bedtime trouble. More on the green tea and guarana profile.
Interactions04
Which medicines interact with Glyco Defender ingredients?
At least nine kinds of medicine have a known interaction with one or more Glyco Defender ingredients. Diabetes drugs and blood thinners top the list.
The amounts in a dropperful are small, so most of these are cautions, not proven problems. A pharmacist can check the full label against your list.
| Medicine | Label lines | What may happen |
|---|---|---|
| Insulin, sulfonylureas, other diabetes drugs | Chromium, gymnema, ginseng, African mango | Added glucose drop (NIH ODS, Chromium) (MSKCC, Irvingia gabonensis (African mango)) |
| Warfarin and other blood thinners | Guarana, forskohlii, ginseng | More bleeding risk (MSKCC, Guarana) (MSKCC, Forskolin (Coleus forskohlii)) (NCCIH, Asian Ginseng) |
| Blood pressure drugs | Forskohlii, arginine, cayenne | Added drop; cough with ACE inhibitors (MSKCC, Forskolin (Coleus forskohlii)) (MSKCC, Arginine) (MSKCC, Cayenne (Capsicum)) |
| Some statins and heart-rhythm drugs | Grapefruit seed | Drug build-up from grapefruit (FDA, Grapefruit juice and drugs) |
| MAO inhibitors, tramadol | L-tryptophan | Serotonin effects (Drugs.com, L-tryptophan) |
| Levothyroxine | Chromium | Less absorbed (NIH ODS, Chromium) |
| Digoxin | Eleuthero | Higher levels, false test results (MSKCC, Siberian Ginseng (Eleuthero)) |
| Immune suppressants | Astragalus | Possible interaction (NCCIH, Astragalus) |
| Corticosteroids | Licorice compound | Reported interaction (NCCIH, Licorice Root) |
The guide to supplements and diabetes medicines covers the lows question in more depth.
Label caution05
Who should not take Glyco Defender?
The label says Glyco Defender is not for anyone under 18 or for pregnant or nursing women. Anyone with a known medical condition should ask a physician first.
Those are the label's own words, printed on the left panel next to the directions. Several ingredients add reasons to ask first.
- High blood pressure, heart or kidney disease: the licorice compound (NCCIH, Licorice Root)
- Autoimmune disease: astragalus (NCCIH, Astragalus)
- Hormone-sensitive cancer: maca (MSKCC, Maca)
- Caffeine sensitivity: guarana and green tea
- Past liver trouble: green tea extract (NCCIH, Green Tea)
Answer five quick questions on the who it's for page.
Glyco Defender: from $49 a bottle30 mL · 1, 3 or 6 bottles · free US shipping on 6 · 60-day money-back guarantee
See packsPets and children06
Is Glyco Defender dangerous for dogs or children?
Yes for dogs. Glyco Defender contains xylitol, which can cause a fast, dangerous drop in a dog's blood sugar within 10 to 60 minutes (FDA, Paws Off Xylitol).
Signs include vomiting, weakness, stumbling, collapse and seizures. If a dog may have licked or chewed the bottle, call a vet or animal poison control right away.
The label also says "Keep out of the reach of children," and the drops are not for anyone under 18.
Keep the cap tight and the bottle in a cabinet, not on a low table or in a handbag a dog can reach.
Liver07
Can Glyco Defender harm the liver?
Liver harm is unlikely at these doses, but two ingredients have rare liver reports. Green tea extracts have been linked to uncommon liver injury (NCCIH, Green Tea).
A reversible liver injury was also reported with gymnema tea (Drugs.com, Gymnema monograph). A dropperful holds at most 2.2 mg of green tea extract and 1.9 mg of gymnema, from the label order.
If you have had liver disease, show the label to your doctor first. Tell your care team about every supplement you use (NCCIH, Using Dietary Supplements Wisely).
What to do08
What should you do if Glyco Defender gives you a side effect?
Pause the drops, write down what happened, and call your doctor or pharmacist. For a severe low or a collapse, call 911.
Pausing a supplement is fine. Prescription drugs stay on the schedule your doctor set unless your doctor changes it.
Pause the drops
Set the bottle aside, with the cap tight, out of reach of pets.
Write it down
Note the time, the symptom and any meter reading.
Call a professional
Your doctor or pharmacist can judge the cause.
Ask about a refund
The 60-day guarantee runs from purchase. Have your order ID ready and call +1 (302) 200-3480.
Guarantee steps are on the 60-day guarantee page.
FAQ09
Glyco Defender side effect questions
Can Glyco Defender cause headaches?
It might in some people. Too much caffeine can cause headaches, and the drops contain caffeine from guarana and green tea with no amount printed. African mango has also been linked to headache in studies. If headaches start after you begin the drops, pause them and talk to your doctor.
Can Glyco Defender keep me awake at night?
Possibly, if you are sensitive to caffeine. Guarana and green tea add caffeine, and insomnia is the most common side effect reported for Panax ginseng. Take the dropperful in the morning, and count it alongside your coffee and tea. The label sets no time of day.
Can Glyco Defender cause low blood sugar without diabetes medicine?
No report links the drops to lows on their own, and no trial has tested them. Lows are mainly a risk with insulin, sulfonylureas and meglitinides. Chromium does not appear to change glucose in healthy people. If you feel shaky, dizzy or confused, check your blood sugar.
Is Glyco Defender safe with high blood pressure?
Ask your doctor first. The licorice compound glycyrrhizin can raise blood pressure, and people with high blood pressure may be at risk even from small amounts. Caffeine from guarana and green tea can also speed your heart. Several ingredients may also add to blood pressure medicines.
Does Glyco Defender upset the stomach?
It can in sensitive people. Cayenne extract may irritate the stomach, caffeine can cause an upset stomach, and African mango has been linked to gas. Amounts per dropperful are small. If your stomach reacts, pause the drops and ask your doctor or pharmacist about it.
What should I do if my dog drank Glyco Defender?
Call a vet or animal poison control right away. The drops contain xylitol, which can cause a dangerous drop in a dog's blood sugar within 10 to 60 minutes. Watch for vomiting, weakness, stumbling or seizures, and bring the bottle so the vet can read the label.
Does the Glyco Defender guarantee cover side effects?
The guarantee is a 60-day money-back offer counted from the date of purchase, sold as a satisfaction refund. Call +1 (302) 200-3480 or email [email protected] with your order ID, then mail the bottles back with tracking. Return postage is on the buyer. See a doctor about the symptom itself.
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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