A novel differentially fed fractal antenna coated with a layer of a dielectric film and operating at two bands of Medical Implant Communication Services 402–405 MHz and Industrial, Scientific, and Medical 2.4–2.48 GHz, is investigated to enable sufficient data transmission rates, while featuring a ‘mode‐control’ signal to prolong the battery life. The symmetrical fractal technology of Hilbert curve is employed to miniaturise the dimension. To facilitate interfacing with peripheral integrated circuits, differentially feeding is adopted. To demonstrate how common‐mode noises are suppressed, for the first time, a detailed analysis about the noise suppression of the differential configuration with two feedings is presented. A layer of thin film is coated around the proposed antenna to isolate the effect of human tissues and alleviate the electromagnetic coupling with human body. Moreover, to draw a design methodological guideline, the key geometrical parameters are analysed numerically and theoretically. Health safety considerations, radiation performance, and link budgets are also discussed to validate the proposed antenna's applicability in biomedical telemetry.