What Is Anhydrous Caffeine?

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Anhydrous caffeine is caffeine that contains lower amounts of water. Anhydrous caffeine contains 0.5 percent or less water, while hydrous caffeine contains up to 8.5 percent water. The powder is only slightly soluble in water. It is a dry, odorless, white crystalline product with a bitter taste.

Weight Loss Products

The dry powder can be further compressed into pellets or granules, and is used for its stimulant effect in tablets, capsules and drinks. Anhydrous caffeine is a commonly and conveniently added ingredient to commercial weight loss pills. It is also added to energy drinks that are designed to promote your mental and physical performance. Caffeine can affect you in this way if you take it in moderate doses between 3 to 6 milligrams per kilogram, or 2.2 lbs, of your body weight.

How It Works

Caffeine, most of which is extracted from natural sources, is considered a mild nervous system stimulant that can be habit-forming. It is not an addictive substance, however. Young people and smaller individuals may be more sensitive to its effects. Studies involving athletes indicate that you would probably get a bigger boost of energy from taking anhydrous caffeine than drinking coffee, especially for high-intensity or maximal endurance exercise.


Caffeine is extracted from tea leaves and poor quality coffee beans. It is also a by-product of decaffeinating coffee beans. Decaffeination is accomplished either by using carbon dioxide or very hot water. Since natural sources are in plentiful supply, there is no need to synthesize caffeine, a process which costs more than extraction. Because pure caffeine is toxic, suppliers may not sell it to individual purchasers. The lethal dose for adults is thought to be 10 grams or 0.35 ounces.


Despite the toxicity of caffeine, there are not many people who are known to have died from caffeine poisoning. Swallowing or inhaling the powder can cause an overdose. Symptoms of overdose include nausea, vomiting, stomach pain, headache, dizziness, rapid pulse, low blood pressure, insomnia, convulsions, shortness of breath and collapse. High doses of caffeine would cause you to start vomiting long before levels in your blood became too high.