Ingredient
Guarana in ZenCortex: What the Label and the Research Say
Guarana is the third of 22 lines in the ZenCortex Proprietary Herbal Blend, a seed extract that contains caffeine. By label order it can weigh at most 66.7 mg per 1 mL serving. The label prints no caffeine amount, which makes the info page's "No Stimulants" line hard to square. Ask a doctor if you take stimulants.
Written by the ZenCortex label deskUpdated
The ingredient01
What is guarana in ZenCortex?
Guarana is the seed of an Amazon vine, and ZenCortex lists it as "Guarana (Paullinia cupana) Seed Extract". It is line 3 of the 22 in the blend.
Memorial Sloan Kettering says the seeds contain caffeine and similar compounds, and that many of guarana's effects are credited to its caffeine (MSK, Guarana). It is used for appetite, fatigue and energy, which is why it appears in energy drinks.
That makes guarana the clearest caffeine source in the formula. Green tea extract, line 7, adds more. Both are covered in the stimulant discussion below.
| Name on the label | Guarana (Paullinia cupana) Seed Extract |
|---|---|
| What it is | Seed of an Amazon vine; a natural source of caffeine |
| Place on the label | Line 3 of 22 in the 200 mg proprietary blend |
| Amount per serving (1 mL) | At most 66.7 mg per 1 mL serving (label order); 9.1 mg if the 22 lines were split evenly |
| What research used | The cited page gives no caffeine amount; FDA cites 400 mg of caffeine a day as an amount most adults tolerate |
| Strength of evidence | A meta-analysis found guarana no better than placebo for cancer-related fatigue; nothing on hearing |
| Marketed or traditional use | Marketed for energy and focus |
| Main caution | Contains caffeine, so the info page's 'No Stimulants' needs a footnote. High amounts can cause heartbeat changes and high blood pressure; use caution with stimulants and blood thinners. |
Label position02
How much guarana is in ZenCortex?
The label does not say. Guarana sits third, so label order caps it at 66.7 mg per serving, which is 200 divided by 3.
The cap follows from the weight rule for blends (eCFR, 21 CFR 101.36 Supplement Facts). Lines 1 to 3 must each weigh at least as much as the line after them, so three lines together cannot pass 200 mg, and line 3 cannot exceed one third of that.
An even split of the blend would be about 9.1 mg, and the label sets no floor. Two droppers a day would give at most 133.4 mg of guarana extract.
| Place in the blend | 3 of 22 |
|---|---|
| Most per serving | 66.7 mg |
| Even split (for comparison) | About 9.1 mg |
| Caffeine amount printed | None |
Caffeine03
Does ZenCortex contain caffeine, and is it a stimulant?
Yes, it can. Guarana seeds contain caffeine, and green tea extract does too, so the seller's "No Stimulants" line needs a footnote.
The cited page gives no specific caffeine amount for guarana (MSK, Guarana). We therefore do not guess a caffeine figure for the drops. Whatever the caffeine share of the extract, it can only be part of the 66.7 mg ceiling.
For scale, FDA cites 400 mg of caffeine a day as an amount most adults tolerate, with sensitivity varying by weight, medicines and conditions (FDA, How Much Caffeine Is Too Much?). Caffeine adds up across coffee, tea, soda and any supplement, and the label here gives no number to add.
The label does not print a caffeine amount at all, so you cannot tell.
Evidence04
Does guarana help energy, fatigue or hearing?
A meta-analysis found guarana no better than placebo for cancer-related fatigue, with low-quality evidence (MSK, Guarana). Nothing links it to hearing.
Other findings from animals and lab work are preliminary. So short-term alertness is plausible through caffeine, but the research on guarana as a treatment is thin.
Caffeine and ringing are a separate matter. We found no source in our set on caffeine and tinnitus, so we make no claim. Ringing that persists deserves a hearing test (NIDCD, Who Can I Turn to for Help with Hearing Loss).
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See packsCautions05
Who should be careful with guarana?
People who use stimulants, blood thinners, or who are sensitive to caffeine should ask a clinician first. Memorial Sloan Kettering urges caution when combining guarana with stimulants and notes antiplatelet activity that may raise bleeding risk with warfarin (MSK, Guarana).
Common effects are nausea and insomnia. High amounts can cause vomiting, heartbeat changes, high blood pressure and seizures, with case reports of fast heartbeat and seizures after guarana energy drinks. The drops are not an energy drink, but the printed label gives no caffeine amount to judge by.
Caffeine combined with other stimulants can intensify side effects (NIH ODS, Dietary Supplements for Weight Loss). Excess caffeine can bring a fast heartbeat, jitters and poor sleep (FDA, How Much Caffeine Is Too Much?).
Do not change a prescribed dose because of a supplement. Ask your pharmacist, and see ZenCortex side effects.
Marketing check06
Is ZenCortex really a no-stimulant formula?
We cannot confirm it. The info page says "No Stimulants", yet guarana and green tea extract both carry caffeine, a stimulant.
The bottle never makes that claim, and its Supplement Facts do not list caffeine. A fair reading is that the drops may be low in caffeine, but "no stimulants" is not something the label supports. The FTC expects marketing claims to match the evidence (FTC, Health Products Compliance Guidance).
If you avoid caffeine for sleep, heart rhythm or pregnancy reasons, treat these drops as a possible source. Pregnant and nursing readers are already told by the label not to use them.
Keep reading07
Which ingredient page should I read after guarana?
Line 7, green tea extract, is the other caffeine source. Line 4 is African mango.
See maca root for line 1, the supplement facts page for the label, and the ZenCortex price guide.
FAQ08
ZenCortex questions people ask
How much caffeine is in guarana?
The sources we cite give no amount. Memorial Sloan Kettering says guarana seeds contain caffeine and many effects are credited to it. The ZenCortex label prints no caffeine figure, so the real amount per dropper is unknown.
Does ZenCortex have caffeine?
It can. Guarana and green tea extract, lines 3 and 7, both carry caffeine, and the label prints no amount. That conflicts with the info page's "No Stimulants" wording. Check with a clinician if you limit caffeine.
Can guarana cause insomnia?
Insomnia is among its common effects, along with nausea, according to Memorial Sloan Kettering. If you are sensitive, take droppers early in the day, as the info page's before-breakfast and before-lunch timing suggests, or skip them.
Is guarana safe with a blood thinner?
Ask your doctor. Memorial Sloan Kettering notes antiplatelet activity that may raise bleeding risk with warfarin. Keep taking your blood thinner exactly as prescribed, and show your pharmacist the bottle.
What is the most guarana in one ZenCortex dropper?
At most 66.7 mg, which is 200 mg divided by 3, because guarana is listed third. An even split would be about 9.1 mg, and the label sets no floor. The label prints no amount, so the exact figure is unknown.
Does guarana help tinnitus?
No source we found says so. The NIDCD says no supplement has been proven effective for tinnitus (NIDCD, Tinnitus). If ringing is new or in one ear, see a clinician, not a supplement aisle.
Who wrote this09
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 Thezencortex, a retailer of ZenCortex, not by the manufacturer. We earn money when you buy through our order links.
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