Abstract: An ingestible gastrointestinal capsule (GIC) for mechanically stimulating a segment of the gastrointestinal (GI) wall by alternately and repeatedly pressurizing, and/or vibrating it is provided. The GIC is programmed to being activated following a predefined time delay. The activated GIC agitates, shakes, rattles, jolts, vibrates and/or moves in a reciprocal expanding and contracting motion thereby mechanically stimulating the adjacent segment of the GI wall at a targeted location. Activation of the GIC may include a number of automatically accomplished partial activations, such as when the time elapsed from the moment of setting the GIC on equals a predefined time delay; when the mechanical load applied onto the GIC exceeds, and/or gets lower than a respective predefined level of mechanical load; when the ambient pH reaches a predefined level, or changes, and/or a temperature associated with the user reaches a predefined threshold. Agitation is accomplished by means of agitation means embedded in the GIC.