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  • For anytime energy and improved focus*
  • Supports amino acid intake with 5 g of amino acids per serving
  • 100 mg of Caffeine
From £19.99

Product Overview


With Optimum Nutrition ESSENTIAL AMIN.O. ENERGY you can get the energy + focus to achieve your goals and take on whatever life throws at you. ESSENTIAL AMINO ENERGY is scientifically designed to support your energy needs and your long-term training.

One serving of ESSENTIAL AMIN.O ENERGY increases energy and alertness with 100 mg of caffeine from natural sources and a burst of flavour you’ll look forward to mixing into cold water anytime.Take a 30-serving tub along to the gym or your office – wherever your busy day takes you.


Ready-to-mix Amino Acid Food Supplement Powder with Caffeine and Vitamin C, with sweeteners.

*Vitamin C contributes to normal energy-yielding metabolism. Caffeine contributes
to increased alertness and improved concentration.


  • 5 g of Amino Acids per serving

  • 100 mg of Caffeine
  • Vitamin C
  • Anytime Energy
  • Improved Focus

Suggested Use

Add 2 level scoops (9 g) to 330 ml of cold water and mix.

*Food supplements are not to be used as a substitute for a varied diet. Do not exceed the recommended daily dose. Keep out of reach of children. Contains caffeine (100 mg/serving). Not recommended for children or pregnant women.

Nutritional Information

Nutritional information will be shown when a flavour and/or size is selected.

Customer Reviews

Overall Rating (4.7)
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Very good

Review by Jordan on Nov 12, 2021
Gives me a good boost of energy to get though the afternoon

Very Good

Review by Js on Oct 20, 2021
It gives me a good booster of energy through my day


Review by Adam Antolec on Oct 1, 2021
Great taste, amazing results and even better price!

Amino energy

Review by Morgen on Sep 30, 2021
A coworker turned me on to this!! Love the taste so much and gives me the pick up I need in the evening at work rather than coffee which just makes me crash and I don’t think coffee even affects me haha. I will continue to buy this! Thanks!

Great Taste and Energy Booster

Review by Tony Quinn on Sep 15, 2021
I get mine in Fruit Fusion flavor. It's so good, the energy boost almost seems like a bonus. It helps get me started after short nights and keep me going on long days.

So yummy

Review by Cyn on Sep 14, 2021
I use both the orange and grape flavors of this product and love each. The flavors taste like popsicles and are not at all medicine-y. it dissolves quickly and leaves no grit. Good stuff!

Helpful and flavorful boost

Review by Sarah Mitchell on Sep 7, 2021
I have been enjoying the energy boost and love the flavor of the many flavors I have tried. I have found the green tea to be a good addition to my diet & not the niacin found in so many other energy drinks. I too would love to see a mix pack, a trial pack of sorts, to try new flavors. Maybe a 'make a mix' box or something.

Take it every morning

Review by John Kriskey on Sep 6, 2021
Been a Optimum Nutrition customer for over a couple of decades and have seen many products disappear and new ones added, I have been taking this every morning for the past several years and I can’t believe how much it’s helped me

Fruit punch

Review by Ashley Sullivan on Aug 9, 2021
Love this stuff my whole family loves it! We always get the grape and fruit punch which are our favorites sometimes I like to mix them together for a different flavor. I also have the blue raspberry which is amazing too. One thing I would recommend is a sample pack which each flavor cause I would like to try other flavors but don’t want to buy a huge jug and not like it:) I like to mix this before leaving work so when I get home I can workout cause it does help with not feeling blah during your workout! Gives good energy. And my husband is a huge diet Mountain Dew soda drinker and he has switched to this cause he likes it and I am so glad he has!

I love this stuff

Review by Cyn on Jul 11, 2021
My most pleasant surprise with this product is the flavor. So far I've tried grape, blue rasp, and orange and I've reordered both grape and orange. The flavors more mimic popsicles than medicine and are quite pleasant. The other thing I really like is that it dissolves quickly and 100%. There's no grit, no gross about it. I take sometimes as a pre-workout, others post, but no matter when it gives me boost I need and is just another ON product that I love.

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