NATURAL STACKS Smart Caffeine Pills – 100mg Caffeine + 200mg L-Theanine Supplement – Supports Energy and Focus – No Jitters and No Crash – 60 Capsules | ⭐ Flexiology.Store Recommended
$19.95
🌿 Expert Tip: Handpicked for natural health, wellness & beauty.
Price: $19.95
(as of Oct 02, 2025 17:22:13 UTC – Details)
From the brand
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Is Discontinued By Manufacturer : No
Product Dimensions : 3.94 x 3.94 x 3.94 inches; 1.76 ounces
Date First Available : November 27, 2013
Manufacturer : Natural Stacks
ASIN : B00GXPNEUO
Best Sellers Rank: #41,830 in Health & Household (See Top 100 in Health & Household) #173 in Sports Nutrition Endurance & Energy Supplements
Customer Reviews: 4.3 4.3 out of 5 stars 618 ratings var dpAcrHasRegisteredArcLinkClickAction; P.when(‘A’, ‘ready’).execute(function(A) { if (dpAcrHasRegisteredArcLinkClickAction !== true) { dpAcrHasRegisteredArcLinkClickAction = true; A.declarative( ‘acrLink-click-metrics’, ‘click’, { “allowLinkDefault”: true }, function (event) { if (window.ue) { ue.count(“acrLinkClickCount”, (ue.count(“acrLinkClickCount”) || 0) + 1); } } ); } }); P.when(‘A’, ‘cf’).execute(function(A) { A.declarative(‘acrStarsLink-click-metrics’, ‘click’, { “allowLinkDefault” : true }, function(event){ if(window.ue) { ue.count(“acrStarsLinkWithPopoverClickCount”, (ue.count(“acrStarsLinkWithPopoverClickCount”) || 0) + 1); } }); });
💡ALERT FOCUS AND PRODUCTIVITY: Take this Smart Caffeine Supplement with L-theanine for when you need alert focus and long lasting energy. We blended 100 mg of the purest form of Caffeine with 200mg mg of L-Theanine from Green Tea to get the best of both worlds.
🚫 NO JITTERS OR CAFFEINE CRASH: Unlike the 200mg caffeine pills that make you jittery and anxious, Smart Caffeine is a calm and smooth energy pill. No more staying up late, wired up from your last cup of coffee too many.
☀️ START YOUR DAY OFF STRONG: Add Smart Caffeine to your morning routine or anytime of day as a study aid, pre-workout or whenever your energy needs a lift. Perfect as a coffee or energy drink replacement.
🌿HEALTHY AND SAFE: Our all ingredients are Non-GMO, gluten free, and vegan. Every ingredient can be traced directly to trusted suppliers.
Brain Health Supplement from a Trusted Open-Source Company: Natural Stacks goes beyond the standard brain supplement requirements to assure customers of the commitment we have to transparency. By being open-source, we promise ingredient traceability, 3rd party lab testing & full label disclosure.
Customers say
Customers find these caffeine pills effective without jitters, providing steady energy for hours and serving as a great alternative to coffee. The supplements help maintain focus for extended periods and improve mental acuity, with one customer mentioning it helped them complete their master’s thesis. While the product receives positive feedback for its quality and effectiveness, opinions on value for money are mixed, with some finding it good but expensive.
🌿 Expert Tip: Selected by our Flexiology Experts for quality & value.
⚠️ Disclaimer: Information is for educational purposes and not a substitute for medical advice. Consult your physician before use. Flexiology.Store is not responsible for any adverse effects.
8 reviews for NATURAL STACKS Smart Caffeine Pills – 100mg Caffeine + 200mg L-Theanine Supplement – Supports Energy and Focus – No Jitters and No Crash – 60 Capsules
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The Rebecca Review –
An Energy Boost Just When You Need It!
Are you exhausted and mentally plus physically worn out? Life can do that to you and sometimes you need a little boost of caffeine energy to get through another day. I was feeling emotionally worn out from dealing with a situation that was not resolving itself and I was having low motivation to get things done.Then I remembered I had these capsules and figured one couldn’t hurt. I will say these do give you an energy that is more long lasting and it didn’t make me feel anxious or wired and I felt no crash besides that I ended up going to bed a little earlier that night.I’d say from the time I took one capsule to the moment I got active was about 20 minutes. I cleaned my whole kitchen, did several loads of laundry and did other things around the house that needed to be done. I literally felt like all the negative emotions I’d been feeling dissolved into a sense of happiness and peace.I will however say that you don’t want to take these if you are not near a restroom because I found out these have a diuretic effect like coffee. Make sure to drink plenty of water even if you only take one capsule. I am not a doctor, nor is this medical advice. Some people also can’t handle much caffeine due to heart or anxiety issues. So use with caution.But overall I felt these were safe enough for me and did give me more energy than a cup of coffee. I personally would not take more than one capsule at a time during a day and would not take these every single day. I consider these more a last resort when I’m really low on energy or feeling emotionally drained. For that they work like a miracle!~The Rebecca Review
Joy –
Stick with it past the first few days, it really works!
As with some of the other posters who mentioned a headache or feeling the need to take a nap mid-day when beginning this product, I felt the same way. However, I kept going with it and I no longer experience those symptoms. I assume it is your body’s way of adjusting to the supplement and shift in caffeine type. Just like with anything there is an adjustment period. Now this is all I need to get me through the day. I no longer have crashes and can steadily focus on my work without the need to make tea or coffee every morning that involves sugar, which I have been off of now for 4 weeks.
Bonnie W. –
Great Product
Currently trudging my way through grad school while working, and often find myself with low energy and unable to focus. Must be the lack of sleep huh? Wrong. Despite being extremely busy, I usually average about 6-8 hours of sleep per night, the exact same amount I had before I went back to grad school. Because of this, I figured I would get something relatively natural and low impact to help increase my energy and focus. I opted for this particular brand because the reviews were pretty good, the packaging and marketing looked rather legit ( I know this may seem like a crazy thing to go off of, but with vitamins if they look like they belong in an infomercial, I feel nervous.) and the price was right. I got them in the mail, and within a week I noticed that I had increased energy, and after two weeks I saw that it was even more intensified. With that said, I still hadn’t seen any improvement in focus, so I decided to “stack” (new supplement lingo I learned from a guy at a health foods store) another supplement, called NootropX – 90 caps – Mental Focus and Concentration Supplement With Memory Enhancement For Extreme Clarity and Alertness – Instant Brain and Memory Power Boost From Patented AES® Absorption System – The Ultimate Brain Vitamins which is a little bit more geared towards the focus aspect I was looking for. After two weeks of taking both of those, I noticed that I was performing better at school and work, and I had the energy to do even more than I had hoped for. My work was coming out better, as I had been able to focus more. I definitely recommend this supplement to anyone who is looking for an energy boost, and even though it didn’t give me a boost in focus, it’s still a great product and since everyone’s body is different it may work for you!
The Illusive Reviewer –
Morning Coffee Substitute or Complement
These pills are great! I used to drink coffee all the time but can’t anymore due to stomach issues. Tea does not do enough and soda is not as healthy. As such I looked into caffeine pills.This brand packs a good little punch that lasts all day and doesn’t make me crash or feel jittery. I have an hour commute to work and an hour back and these pills keep me awake and focused. They are easy to swallow and no taste.Also, I find I am able to take more caffeine such as maybe espresso with this and still feel okay. I would recommend taking it before your morning shower to let it kick in. As another note, these pills do not cause me any GI issues like coffee does.Pros: easy to swallow, keeps me focused, no jitters or crashCons: effect dissipates after constant use, sometimes causes anxiety (infrequent)
Sheri –
No jitters packed with energy
This is has made a huge difference in my daily life. Definitely has increased my energy without feeling shaky.. I would recommend this ; just be aware not to take it in afternoon. It will def affect your sleep; stop taking at least 5 hours before bed
Cory –
Here’s why it might not work for you
You might not get a boost from this if your brain is sensitive to L-Theanine. You might actually have the reverse affect and get a little sleepy in spite of the caffeine. I’m the type that gets sleepy if I take L-Theanine so these pills put me to sleep. L-Theanine is great, but for some brains it’s calming effect makes them super drowsy. You will have to experiment with this. For those of you who need the L-Theanine, I’ve heard the combo with caffeine works great. For me, unfortunately, it doesn’t work.
Paula –
No go
Going from regular caffeine pills to this made me sad. It was like a sleeping pill. not smart for me. We all react differently to substances. Maybe for someone else it works great. I also have chronic fatigue syndrome, so maybe i just need a bigger kick. This was a fail for me
Marilynn Stocking –
It works
Absolutely Love it !!!!!Easy To SwallowVery Effective