The study aimed to evaluate the effects of adding nalbuphine to bupivacaine for spinal anaesthesia in elderly patients, comparing the quality of block, duration of analgesia, and adverse effects. Results showed that the addition of nalbuphine significantly prolonged post-operative analgesia, averaging 8-9 hours compared to 2-3 hours with bupivacaine alone, without adverse effects. The findings suggest that nalbuphine enhances the anaesthetic protocol for elderly patients undergoing lower limb and abdominal surgeries.