Bhagavad Gita
18.38

विषयेन्द्रियसंयोगाद्यत्तदग्रेऽमृतोपमम् | परिणामे विषमिव तत्सुखं राजसं स्मृतम् ||

viṣayendriya-saṁyogād yat tad agre 'mṛtopamam pariṇāme viṣam iva tat sukhaṁ rājasaṁ smṛtam

Translation

That happiness which arises from the contact of the senses with their objects — like nectar at first but like poison at the end — that is declared to be rajasic.

Interpretation

Rajasic happiness is the precise inverse: like nectar at first, like poison in the end. The pleasure of sensory gratification is real and immediately satisfying — the intoxication of desire-fulfillment, the excitement of acquisition, the rush of sensory pleasure. But its aftermath: the hangover, the craving for more, the growing tolerance that requires ever-stronger stimulation, the emptiness when the pleasure fades, the suffering created for others and eventually for oneself. Every addiction follows this pattern: nectar to poison. This is not an argument against pleasure but an invitation to honest accounting of what our pleasures ultimately cost.