Which statement about implantable device restrictions is accurate?

• A. Iontophoresis in higher outputs
• B. MRI is always safe
• C. Electromagnetic fields pose no risk
• D. Regular magnets are harmless near the device

Answer: (A)

Implantable devices carry electronics that can be affected by external electrical and magnetic influences. When a therapy uses electrical currents near the device, those currents can interfere with how the device operates or cause heating near the leads. This is why higher-output iontophoresis near an implanted device is restricted—it increases the risk of electrical interference or tissue heating, so clinicians typically use the lowest effective current, avoid applying iontophoresis close to the device, or choose alternative methods based on the device type and manufacturer guidelines.

In contrast, MRI safety depends on device compatibility and proper protocols; many devices are not safe for MRI unless they are specifically labeled MR-conditional and even then require strict precautions. Electromagnetic fields can pose risks to implanted devices, potentially causing malfunction or reprogramming. Regular magnets can affect device behavior and are not universally harmless near implants.