Integrating the Internet of Things (IoT) with unmanned aerial vehicles (UAV) system enables various value-added services from sky to ground. IoT devices are connected to communicate or exchange information in wireless sensor networks (WSN). Moment of the sensor in UAV, data transmission and data sensing processes are consuming more energy in WSN. This data transmission process takes a higher amount of energy than other processes of IoT-based UAV devices. It is an open challenge for researchers to optimize energy consumption during data transmission whenever an emergency occurs. So, this research focuses on developing an energy-efficient emergency response Routing Protocol for Low-power and Lossy networks (EEER-RPL) to prolong the network lifetime of the IoT network. It is achieved by electing the Super Nose (S.N.) during the emergency message transmission. The S.N. election process is performed by calculating the distance among all neighboring nodes. A node with optimum distance and higher energy is considered as S.N. to transmit data among its neighboring nodes. In this, the S.N. acts as a normal node in the standard data transmission process. Whenever the network gets the emergency signal, it selects S.N. to perform energy efficient Routing. The Simulation results show that the proposed EEER-RPL outperforms the existing schemes regarding network lifetime, average packet delivery time, and average hop selection.