Silver and/or zinc ion releasing implants, systems and method of operating, inserting and activating/inactivating them are described. In some variations the implant is configured as a bone implant that includes a bone-screw or intramedullary rod like body configured to receive a treatment cartridge having a plurality of ion-releasing members configured as an anode that can controllably engage with a catheter to turn galvanic release of ions on/off as desired. These devices may be configured to release silver ions (and/or zinc ions) above a predetermined level for a predetermined period of time and may maintain a concentration of ions over a relatively large volume of tissue. The ion-releasing members may be configured to reduce or prevent implant movement.