Caffeine may be the most popular legal addictive stimulant that is available to mankind. Besides coffee, tea, guarana and kola nut have excess amount of this xanthine alkaloid, which is actually acting as a psychoactive drug. In several plants, caffeine is an effective insect repellant, but this trimethylxanthine is deemed by the Food and Drug Administration as generally safe food substance. It is an antagonist of adenosine receptors. The effect of caffeine is individual and may more or less increase the ability to perform physical and mental labor. It reduces the effects of fatigue and may in long term help predominantly men reduce the risk of developing Parkinson’s disease. It has also been observed that caffeine has nootropic effects, furthermore, regular consumption of caffeine may significantly reduce the risk of heart diseases.

Green Tea Extract comes from green tea leaves and has been shown to be a very effective supplement for many common ailments ranging from minor to life threatening. Green tea extract is known for its strong antioxidant qualities, making it popular amongst those who take an active role in ensuring their good health. In fact, green tea extract has twenty times more antioxidants than the same portion of Vitamin C, another clouted supplement for health aficionados. In addition to antioxidants, green tea extract is effective at fighting carcinogens and inflammation. Green tea extract is best known for fighting cancer when combined with other methods, for reducing inflammation, and for encouraging overall good physical health.

Guarana is not only a dietary supplement but also an energy booster as well as it has a high concentration of caffeine.

Kola Nut has a euphoric and stimulating effect on the heart and central nervous system and produces a heightened state of euphoria and well-being.

Methylxanthines (Caffeine) is basically a type of bronchodilator, methylxanthine is considered highly effective in the treatment of COPD. Due to its ability to relax the airways, it enables the patient to breathe more easily. For the same reason, it is believed to improve respiratory muscle strength when administered orally or intravenously. Caffeine, a widely used psychoactive substance, belongs to this group of compounds called as methylxanthines. Caffeine gives rise to number of neurological side effects such as anxiety, insomnia, restlessness, and tachycardia. On the other hand, low to moderate consumption of caffeine can lead to positive effects such as enhanced alertness, energy and better concentration. Some people may experience withdrawal symptoms after about 12 to 24 hours after sudden cessation of caffeine consumption while some individuals may report of such symptoms within 3 to 6 hours.

Theobromine, which is a mild diuretic and mild stimulant. Theobromine can be found in cocoa and chocolate products. Theobromine is most commonly used for its diuretic effect.

Theophylline is a drug which belongs to the xanthine family. These substances are aromatic in nature and consist of a purine ring which is substituted with different chemical groups at different carbon positions to form different compounds chemically. In case of theophylline the purine ring has one methyl group substituted at carbon number 1 and 3 and one oxygen atom substituted at carbon number 6 and 2. Theophylline was originally extracted from tea leaves and was initially used to increase the rate of urination (diuresis); later it found more uses as a drug because of its effects on the respiratory and circulatory systems. However, it has many side effects; therefore, presently it is prescribed quite judiciously.