A bitter white alkaloid, C8H10N4O2, often derived from tea or coffee and used in medicine chiefly as a mild stimulant and to treat certain kinds of headache.

Kucha(Camellia assamica var. kucha) is a special wild tea resource, containing 1,3,7,9-tetramethyluric acid(theacrine) as the predominant purine alkaloid in the leaves.