Pharmaceutical compositions containing a magnetically detectable material

Claim 1

A pharmaceutical composition in unit dosage form for administration to the gastrointesinal tract of a patient comprising a pharmacologically active agent and a magnetic material, said magnetic material, when present in the gastrointestinal tract of the patient, being capable of reacting to an externally applied magnetic field to produce a magnetic signal which is selectively detectable by an electronic monitoring device, and thereby providing verification that the composition is present in the patient's gastrointestinal tract and further providing an indication of the location of the composition in the patient's gastrointestinal tract, the magnetic material being a material which exists prior to administration of the composition to the patient's gastrointestinal tract in a first state which does not produce the selectivity detectable magnetic signal but which undergoes transformation in the gastrointestinal tract, as a result of the action of the gastrointestinal environment, to a second state which does produce the selectively detectable magnetic signal, the magnetic material being a wire, tape, strip or film which in the first state is folded into a magnetically undetectable configuration and which in its second state is unfolded into a magnetically detectable configuration.