The Use and Safety of Caffeine Anhydrous

Supplement powder and pills coming out of bottles

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With caffeine anhydrous products gaining popularity at supplement stores, you may wonder if you should trade in your morning cup of joe for a caffeine pill. 

While caffeine anhydrous can help improve alertness and exercise performance, it’s not without risk.

Taking too much can cause some scary side effects and even a potential caffeine overdose.

Don’t panic though. The key to using caffeine anhydrous safely is selecting a quality product, avoiding pure powders, and being absolutely certain you stick to the correct dosage. Or, simply stick with natural caffeine like coffee and tea. These can be equally effective and present far fewer safety concerns.

What Is Caffeine Anhydrous?

Caffeine is a naturally occurring substance found in approximately 60 different plant species. You’re probably familiar with common plant sources of caffeine in food and beverages, like:

  • A warm mug of green tea (tea leaves)
  • Delectable squares of dark chocolate (cacao)
  • Your favorite cup of dark roast java (coffee beans)

Caffeine anhydrous is derived from these plants. The other chemical components of the plants along with any water are filtered out in a laboratory. This leaves a white crystalline powder called caffeine anhydrous.


The most common forms of caffeine anhydrous are pills and powders. However, the FDA advises avoiding any pure powders. There is a fine line between a safe and unsafe dose, and a small mistake in measurement could lead to dangerous side effects.

In addition to standalone powders and pills, caffeine anhydrous is frequently used as an ingredient in various supplement categories. For example, you may find it in a pre-workout powder or in pills that claim to burn fat. Certain food products also contain added caffeine anhydrous, such as caffeinated energy bars or chewing gum.

When you're looking at supplement labels, you might run across forms of caffeine anhydrous that are combined with other chemicals. These include:

  • Caffeine Citrate: This is a combination of caffeine anhydrous and two other chemicals—citric acid monohydrate and sodium citrate dihydrate. Caffeine makes up about half of the combination. Caffeine citrate is more commonly used for medical purposes rather than supplementation. In particular, it’s used as a treatment for a breathing problem among premature infants.
  • Caffeine Pterostilbene Co-Crystal: This is a combination of caffeine and pterostilbene, an antioxidant found in blueberries. It may be manufactured into several forms like capsules, tablets, or chews. Manufacturers claim that this form of caffeine creates longer-lasting energy, but this has not been proven in scientific studies.
  • Dicaffeine Malate: This is made of two caffeine molecules attached to a molecule of malic acid. Malic acid is an organic acid that is found in many foods you eat, like apples. Manufacturers of this ingredient claim that combining caffeine with malic acid prevents stomach upset, but this has not been proven.

How It Works

Caffeine works the same way whether it's from a natural source or caffeine anhydrous. It's a sneaky impersonator of another chemical in your brain—a neurotransmitter called adenosine. When adenosine latches on to certain receptors in the brain, it makes you slow down and feel sleepy.

That mid-afternoon lull that you hit? You can thank adenosine for that. But caffeine is structurally similar to adenosine. When you ingest caffeine, it attaches to those same receptors and prevents as much adenosine from binding. This keeps you feeling awake and alert longer.

Impact on Exercise Performance

Caffeine—anhydrous or natural—is well established as a performance enhancer. Numerous studies and reviews have found that caffeine enhances endurance performance in activities like running and cycling. A review of 12 meta-analyses in the British Journal of Sports Medicine (that primarily studied caffeine andhyrous in capsule form), found that caffeine improved muscle strength and endurance. It also had a greater impact on aerobic exercise than anaerobic exercise.

While there is no standardized approach to caffeine administration in exercise research, the large majority have used caffeine anhydrous capsules. In research, it’s easier to standardize a dose this way. Cups of coffee or tea can vary in caffeine content depending on the type and brewing time, but capsules provide an exact dosage.

Coffee vs. Caffeine Anhydrous

Don't rush out to grab caffeine anhydrous pills just yet though. Recent studies have attempted to clarify whether or not coffee can be equally effective for athletic performance as caffeine anhydrous. Since coffee is inexpensive and considered safer, it's a preferable choice for many.

There are two pieces of research worth highlighting:

  • A study comparing the same dose of coffee to a caffeine anhydrous dose concluded that there was no difference between the two forms of caffeine on the sprint performance of 56 men.
  • A study on elite male cyclists found no difference in the performance-enhancing effects of 5 mg/kg caffeine whether it was through coffee or through caffeine anhydrous.

While data is still lacking on other types of exercise, it appears that sipping on that brew before your cardio sessions will help give you that extra kick.


If you're planning to use caffeine as a performance enhancer, try following these guidelines to give you that added oomph:

  • Always start at the lower end of that range and find the minimum dose that helps you to achieve the performance boost.
  • Consume the caffeine about an hour before your training session or event.
  • Keep in mind that doses over 6 mg/kg do not provide any additional benefits, and may cause side effects and safety concerns.
  • Stick with a pre-exercise dose of caffeine (natural or anhydrous) around 3-6 mg/kg of body weight.

For a 150-pound athlete, a 3 mg/kg dose corresponds to around 200 milligrams of caffeine, equivalent to about two cups of coffee.

If you decide to use anhydrous caffeine capsules instead, you can find many varieties on the market that provide this amount. Be sure to check the label to see the proper dosage, as levels can vary based on the manufacturer and product line.

Regulation by Athletic Organizations

Whether anhydrous or naturally-occurring, caffeine is regulated by some athletic organizations.

National Collegiate Athletic Association (NCAA)

If you’re a collegiate athlete, you’ll want to tread carefully with caffeine intake. The NCAA 2019-2020 list of banned stimulants includes caffeine, using a threshold of 15 micrograms per milliliter in the urine. This is equivalent to approximately 500 milligrams of caffeine (or about 6 cups of coffee) consumed at one time.

World Anti-Doping Agency (WADA)

If you’re a professional athlete, you can breathe a sigh of relief. The WADA does not currently consider caffeine a banned substance. While it appeared on the list from 1984 to 2003, it was removed due to concerns that the threshold could not differentiate habitual dietary patterns (for example, frequent coffee and soft drinks) versus those using it as a performance enhancer.

WADA does include caffeine on their “monitoring program.” This program is designed to track substances that are not currently prohibited but risk being misused or abused by athletes.

It is plausible that it could be added back to the banned substance list in the future, likely at a threshold of 12-15 micrograms per milliliter in the urine. For most athletes though, use at the performance-enhancing dose of 3-6 mg/kg should not produce urinary levels over this level.

Safety Guidelines

According to the FDA, most adults can safely consume up to 400 milligrams of caffeine. The European Food Safety Authority also supports this level of consumption, stating that single doses of 200 milligrams at one time and habitual consumption of 400 milligrams per day are considered safe for non-pregnant women.

This safety level is applicable for either natural or anhydrous caffeine. 

A 400-milligram daily dosage of caffeine—which is considered a safe amount—is equivalent to about four cups of home-brewed coffee, or two caffeine anhydrous pills that contain 200 milligrams each.

There are additional safety concerns with caffeine anhydrous products compared to natural sources, though. You'll want to pay attention to these guidelines:

  • Always check with your doctor prior to beginning any supplement. Your doctor will have a clear picture of your current medical conditions and medications and will be able to tell you if there are reasons you should limit or avoid caffeine anhydrous.
  • Avoid pure powdered caffeine. As mentioned, the FDA recommends avoidance due to the ease of accidental overdose. A single teaspoon of pure powdered anhydrous caffeine is enough to cause potentially fatal consequences, as it's equivalent to 2700 milligrams of caffeine. To put that in perspective, you’d have to drink 28 cups of coffee, 68 cups of black tea, or 68 cans of cola to ingest the same amount of caffeine.
  • Choose other forms and understand the dosage. Selecting another form of caffeine anhydrous, like capsules, should make it easier to stay within the safety guidelines. Take some time to check the bottles to make sure you understand just how much caffeine is in each pill.
  • Look for reputable manufacturers. Good manufacturers put practices in place to avoid contamination with unwanted ingredients and prioritize supplement safety. Look for NSF or UL certifications on the bottles, both of which are independent third-party organizations that review supplement manufacturing processes.

Side Effects

Your tolerance to different levels of caffeine can depend on your body size, typical consumption, medications, and even your genetics. If you start ingesting more caffeine than the recommended limits, you can experience side effects.

Concerning side effects of heavy caffeine use include:

  • Anxiety
  • Diarrhea
  • Headaches
  • Insomnia
  • Nausea
  • Restlessness
  • Stomach upset

Severe consequences of caffeine intoxication include:

  • Chest pain
  • Death
  • Disorientation
  • Rapid heartbeat
  • Seizures
  • Vomiting

You might feel a bit fearful after learning about these side effects. Take comfort in the fact that it would be quite difficult to see any severe side effects with natural caffeine consumption in food and beverages. You can be confident in your normal dietary choices.

If you decide to take caffeine anhydrous supplements, it's important to be aware that these risks exist. By taking the precautions mentioned above—like discussing use with your doctor and staying at a safe amount—you can minimize any risk.


Yes. If you’re pregnant or breastfeeding, it’s best to avoid caffeine anhydrous completely. Don’t worry – you can still safely enjoy limited consumption of natural caffeine, like a cup of coffee or some dark chocolate each day.

If you’re a parent, you’ll also want to have a chat with your teens about avoiding caffeine anhydrous. Many teen athletes start investigating supplement options for sports or general fitness. However, they may not understand the consequences of excessive supplement use, since these products are seen as “natural.” Be sure you help them realize that caffeine supplements can be dangerous.

In addition, you’ll also want to avoid caffeine anhydrous if you’re taking certain medications. These include stimulants, certain antibiotics, asthma medications, and heart medications.

14 Sources
Verywell Fit uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. U.S. National Library of Medicine, MedlinePlus. Caffeine.

  2. U.S. Food and Drug Administration. Pure and highly concentrated caffeine.

  3. U.S. Department of Defense Dietary Supplement Resource. Caffeine: different names, different forms.

  4. Parikka V, Beck J, Zhai Q, Leppäsalo J, Lehtonen L, Soukka H. The effect of caffeine citrate on neural breathing pattern in preterm infants. Early Hum Dev. 2015;91(10):565-568. doi:10.1016/j.earlhumdev.2015.06.007

  5. U.S. National Library of Medicine, National Center for Biotechnology Information, PubChem Database. Caffeine (CID 2519).

  6. Grgic J, Grgic I, Pickering C, Schoenfeld BJ, Bishop DJ, Pedisic Z. Wake up and smell the coffee: caffeine supplementation and exercise performance-an umbrella review of 21 published meta-analyses. Br J Sports Med. 2019. doi:10.1136/bjsports-2018-100278

  7. Trexler ET, Smith-Ryan AE, Roelofs EJ, Hirsch KR, Mock MG. Effects of coffee and caffeine anhydrous on strength and sprint performanceEur J Sport Sci. 2016;16(6):702–710. doi:10.1080/17461391.2015.1085097

  8. Hodgson AB, Randell RK, Jeukendrup AE. The metabolic and performance effects of caffeine compared to coffee during endurance exercise. PLoS ONE. 2013;8(4):e59561. doi:10.1371/journal.pone.0059561

  9. NCAA, Sports Science Institute. 2019-2020 NCAA banned substances.

  10. World Anti-Doping Agency. 2020 List of Prohibited Substances and Methods.

  11. World Anti-Doping Agency. 2020 Monitoring Program.

  12. European Food Safety Authority. Scientific opinion on the safety of caffeineEFSA Journal. 2015;13(5):4102

  13. Willson C. The clinical toxicology of caffeine: A review and case studyToxicol Rep. 2018;5:1140–1152. doi:10.1016/j.toxrep.2018.11.002

  14. U.S. National Library of Medicine, MedlinePlus. Caffeine in the diet.

Additional Reading

By Chrissy Carroll, RD, MPH
Chrissy Carroll is a registered dietitian and USAT Level I Triathlon Coach, and the author of "Eat to Peak: Sports Nutrition for Runners and Triathletes."