Apparatus for dosage control

摘要

The invention is directed to a dose control apparatus for manipulating the dosage of one or more pharmaceutical solutions emanating from an implantable drug infusion pump. The dose control apparatus has a movable core that is held in a desired position by a magnet. The apparatus has at least one coil that, when activated, motivates the core to move to a new position. The core may be held in the second position by another magnet. The apparatus may have more that one coil provide various control options. In addition, the coils may be used to determine core position or the presence and strength of an externally applied magnetic field such as that produced in an MRI. The coils may also be used to produce a magnetic field counteracting the externally applied field or to produce a degaussing field.