Electromagnetic Fields (EMFs) are invisible forces that represent one of the most common and fastest growing environmental impacts, due to increased EM sources such as radio frequency (RF) systems including mobile phones and various security systems that play an important role in our lives. So it is expected to see a large increase in EMI on electronic devices in general, and in some cases may pose a serious risk to Medical Electronic Devices (MEDs), especially when the devices are close to the source of EMI. MEDs are vital and life-saving devices, especially those implanted in the human body, such as Implanted Pacemaker devices (IPM) and Implanted Cardio-Defibrillator (ICD). These devices, like other electronic devices, are negatively affected by EMFs that interfere with their function and can cause treatment that does not need or withhold the required treatment. If this happens, the patient using these devices may experience unexpected shocks that can lead to his death. The US Food and Drug Administration (FDA) and other sources of experts have noted that interference with MED can result from many daily sources. Therefore, the study of the harmful effects of EMI on IMDs is very important and we will try to provide interested readers with general knowledge regarding EMI and its harmful effects on IMDs, and means to prevent or curb these effects. The aim of this scientific work is to describe, assess and discuss the risk attributable to EMI interactions from the most common sources such as cellular phones and security systems on IMEDs. The methodology used here is descriptive by: Collecting information and data about EMI and their effects on IMDs, which helps in generalizing protection.