Internet-of-Things (IoT) denote a developing era of networking that connects devices to one another as well as with the rest of internet to smarter our lives. IoT in healthcare applications enables medical devices are receiving a request from external devices like smartphones, smartwatches, and smart glass in order to monitor and control the implanted medical devices. These requests are creating several security issues in the form of malicious data packet intrusion into medical devices. Many approaches were introduced to avoid device level attack known as Denial of Service (DoS) attack but these approaches are failed to protect medical devices from hacking. This paper aims to introduce a packet filtering device level firewall to monitor and filtering malicious data packets. The experimental results are shown that proposed mechanism accepts only legitimate data can enter and control the implanted medical devices. The proposed method achieves 20 to 40 percent faster performance than existing work also consumes less energy which is more significant for resource-constrained devices like IoT devices. Copyright © 2018 American Scientific Publishers. All rights reserved.