137trimethylxanthine

137trimethylxanthine, more commonly known as caffeine, is a bitter, colorless alkaloid of the xanthine family. Its IUPAC name is 1,3,7-trimethylxanthine, and its chemical formula is C8H10N4O2 with a molar mass of 194.19 g/mol. It occurs naturally in coffee beans, tea leaves, cacao, and kola nuts, and is also produced synthetically for use in foods, beverages, and medicines.

Caffeine acts primarily as a central nervous system stimulant. It functions as an antagonist of adenosine receptors, especially A1 and A2A, which reduces perceived fatigue and increases alertness. Additional effects may include mild mood elevation, increased heart rate, and diuresis. The compound can enhance certain aspects of cognitive performance in the short term, particularly when sleep-deprived or fatigued.

Pharmacokinetics and metabolism: caffeine is rapidly absorbed after oral ingestion, with peak plasma concentrations typically reached within 30 to 60 minutes. It is metabolized in the liver by the cytochrome P450 system, especially CYP1A2, into several metabolites, including paraxanthine, theobromine, and theophylline, which contribute to its physiological effects. The metabolites are excreted in urine, and the overall elimination half-life in healthy adults generally ranges from about 3 to 5 hours; it can be shorter in smokers and longer during pregnancy or liver disease.

Applications and safety: caffeine is widely consumed in coffee, tea, chocolate, and energy products. It is also used in some pharmaceutical preparations to enhance alertness or as an adjuvant in analgesic formulations. Moderate intake is considered safe for most healthy adults, but excessive consumption can cause insomnia, anxiety, tachycardia, and dependence. Pregnant individuals are usually advised to limit intake.

History: caffeine was first isolated in 1819 by Friedrich Ferdinand Runge from coffee beans. The name derives from the word for coffee, kaffee. It remains the most widely used psychoactive drug worldwide.