In general, drugs play a vital role in our day to day life to heal several diseases. However, higher doses of drug which initiates the side effect and leads to chronic disease. Among the drugs, this occupies a unique position because of its own functional properties. The methylxanthine derivatives are also largely consumed as a psychoactive alkaloid drug that includes Caffeine (C8H10N4O2), Theophylline (C7H8N4O2), Paraxanthine (C7H8N4O2), Pentoxifylline (C13H18N4O3), Theobromine (C7H8N4O2), Aminophylline (C16H24N10O4), and IBMX-3-Isobutyl-1-methylxanthine (C10H14N4O2) and it has been stimulating particular parts of the nervous system in the human body. Especially this drug is consumed in the name of coffee more than 80% of people all over the world without knowingly or unknowingly the impact of caffeine. This paper deals with the effect of functional groups of methylxanthine having -NH2, -C=O2, -CONH2.