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Guarana: The Caffeine Source Listed in ZenCortex
Guarana is the seed of an Amazon vine, used in supplements as a natural source of caffeine. ZenCortex lists it as line 3 of 22, so it can weigh at most 66.7 mg per dropper, and the label prints no caffeine amount. That matters for anyone sensitive to caffeine (MSK, Guarana).
Written by the ZenCortex label deskUpdated · 4 min read
What is guarana, and does it contain caffeine?
Guarana is a seed extract from Paullinia cupana, and yes, it contains caffeine. Memorial Sloan Kettering says many of its effects are attributed to that caffeine (MSK, Guarana).
People use it to cut appetite, ease tiredness and raise energy. In a meta-analysis, guarana was not better than placebo for cancer-related fatigue, and the evidence was low quality.
The same page gives no caffeine amount for guarana, and neither does the ZenCortex label.
Is ZenCortex really "No Stimulants"?
No, not in the plain sense of the word. The info page says "No Stimulants", yet the blend lists guarana and green tea extract, and both carry caffeine.
The bottle makes no such claim. It says only "Supports Healthy Hearing†". The stimulant line comes from the sales page, so treat it as a claim to check, not a fact to rely on.
Caffeine can arrive from sources that do not look like coffee, and a plant seed extract is one of them.
How much caffeine is too much in a day?
FDA cites 400 mg a day as an amount not generally linked with harm for most adults. That is about two to three 12-ounce cups of coffee, or roughly 130 to 200 mg a cup (FDA, How Much Caffeine Is Too Much?).
Sensitivity varies with body weight, medicines and health conditions. Too much can cause a fast heartbeat, jitters, anxiety, headache and poor sleep.
| Source | Caffeine amount |
|---|---|
| Your coffee or tea | Count the cups |
| Guarana in ZenCortex | Not printed |
| Green tea extract in ZenCortex | Not printed |
| FDA reference for most adults | 400 mg a day |
Two blanks in a budget mean you cannot finish the sum. That is the honest limit of the label.
ZenCortex: from $49 a bottle60 mL drops · 2, 3 or 6 bottles · free US shipping on 3 and 6 · 60-day guarantee
See packsHow much guarana is in a ZenCortex dropper?
The label does not print the amount of guarana. It prints one 200 mg total for 22 lines, in order from most to least by weight (eCFR, 21 CFR 101.36 Supplement Facts).
Guarana is line 3, so it can weigh at most 200 divided by 3, or 66.7 mg of extract per dropper. An even split would be 9.1 mg. Extract weight is not caffeine weight, and the share of caffeine in it is not given.
If caffeine bothers you, tell your pharmacist and keep taking prescribed medicine. High amounts of guarana can affect heart rhythm and blood pressure, and caution is advised with stimulants and blood thinners. Read the guarana page and the side effects page, or our post on all-day energy supplements.
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FAQ01
ZenCortex questions people ask
How much caffeine is in guarana?
Sources do not give one fixed number, because it depends on the seed and the extract. The Sloan Kettering page lists no amount, and the ZenCortex label prints none either, so a safe total cannot be worked out from the bottle (MSK, Guarana).
Can guarana keep me awake at night?
It can. Insomnia is among the common effects of guarana, along with nausea. If you are sensitive, ask a pharmacist before using any product that lists it, and notice how sleep changes in the first weeks.
Is guarana safe with other stimulants?
The Sloan Kettering page advises caution when combining guarana with other stimulants, and it notes antiplatelet activity that may raise bleeding risk. Show the label to a pharmacist if you take stimulants or blood thinners (NCCIH, Using Dietary Supplements Wisely).
Who wrote this02
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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