In emergency situations, ensuring the secure transmission of medical information is critical. While existing schemes address on-road emergencies, off-road scenarios present unique challenges due to hazardous locations inaccessible to conventional vehicles. This research introduces a protocol for off-road emergencies, leveraging flying ad hoc networks (FANETs) formed by drones. The protocol, designed for users receiving emergency treatment, employs cryptographic techniques to protect sensitive information. To overcome the challenge of decrypting user medical records at emergency centers without the healthcare provider’s key, proxy re-encryption is employed. The control center (CC) securely generates encryption and decryption keys, facilitating the re-encryption process by the cloud server (CS) and transmission to the emergency center (E). The proposed protocol, free from pairing functions, underwent security and efficiency analyses, demonstrating resilience against chosen-ciphertext attacks (CCA) and collusion resistance (CR). Execution times of approximately 0.02 and 0.0 s for re-encryption and decryption processes, respectively, for a message size of 2000 bytes highlighted the efficiency of the protocol. The research contributes a secure and efficient proxy re-encryption protocol for off-road emergency medical information transmission within FANETs.