1. A class of alkaloid compounds derived from xanthine that stimulate the central nervous system; includes caffeine, theophylline, and theobromine.
Usage: plural form; technical/scientific term; commonly used in pharmacology and chemistry

Examples

• Methylxanthines are found naturally in coffee, tea, and chocolate.
• The pharmacist explained that methylxanthines work by blocking adenosine receptors in the brain.
• Caffeine and theophylline are the most commonly studied methylxanthines.
• Patients taking certain medications should limit their intake of methylxanthines.
• Methylxanthines have been used for centuries in traditional beverages across many cultures.
• The effects of methylxanthines on sleep patterns have been extensively researched.