Majjhima Nikaya 5:23
SUJATOsappasirūpamā kāmā vuttā bhagavatā bahudukkhā bahupāyāsā, ādīnavo ettha bhiyyo”ti.
a snake’s head, the Buddha says that sensual pleasures give little gratification and much suffering and distress, and they are all the more full of drawbacks.”