  Telemedicine refers to the use of information and communication technology to
assist with medical information and services. In health care applications, high
reliable communication links between the health care provider and the desired
destination in the human body play a central role in designing end-to-end (E2E)
telemedicine system. In the advanced health care applications, $\text{e.g.}$
drug delivery, molecular communication becomes a major building block in
bio-nano-medical applications. In this paper, an E2E communication link
consisting of the electromagnetic and the molecular link is investigated. This
paradigm is crucial when the body is a part of the communication system. Based
on the quality of service (QoS) metrics, we present a closed-form expression
for the E2E BER of the combination of molecular and wireless electromagnetic
communications. \textcolor{black}{ Next, we formulate an optimization problem
with the aim of minimizing the E2E BER of the system to achieve the optimal
symbol duration for EC and DMC regarding the imposing delivery time from
telemedicine services.} The proposed problem is solved by an iterative
algorithm based on the bisection method. Also, we study the impact of the
system parameters, including drift velocity, detection threshold at the
receiver in molecular communication, on the performance of the system.
Numerical results show that the proposed method obtains the minimum E2E bit
error probability by selecting an appropriate symbol duration of
electromagnetic and molecular communications.
