Methylxanthiiniryhmä

Methylxanthines are a class of naturally occurring alkaloids found in various plants, most notably in coffee beans, tea leaves, and cacao beans. They are also synthesized for medicinal purposes. The most common and well-known methylxanthines are caffeine, theobromine, and theophylline. These compounds share a similar chemical structure, based on a purine ring system, and exhibit stimulant properties by acting as antagonists of adenosine receptors in the central nervous system. This antagonism leads to increased alertness, reduced fatigue, and improved cognitive function in many individuals.

Caffeine is the most widely consumed methylxanthine globally, primarily known for its presence in coffee, tea, and soft drinks. Theobromine is found in chocolate and is responsible for some of its mood-lifting effects, though it is a weaker stimulant than caffeine. Theophylline is used medicinally, often to treat respiratory conditions like asthma and chronic obstructive pulmonary disease (COPD), due to its bronchodilator effects. While generally safe in moderate amounts, excessive consumption of methylxanthines can lead to side effects such as insomnia, anxiety, rapid heart rate, and digestive issues. Their metabolism primarily occurs in the liver.