The light capsule object of the present invention is an ingestible device designed to illuminate the gastric cavity of the stomach for therapeutic purposes directed against Helicobacter pylori (H. pylori) bacteria. It comprises: a casing transparent to visible light, in turn containing punctiform light sources, preferably constituted by LEDs, positioned immediately under said casing and capable of emitting light at appropriate wavelength bands (preferably 405 nm and 630 nm) a battery, adapted to power the LED sources for approximately 20-30 minutes (the average transit time in the stomach) a switch which allows a delayed power on and allows the tablet to be still &ldquooff&rdquo when it is swallowed. The light emitted by the capsule strikes the H. pylori bacteria anchored on the gastric wall. The light radiation is preferentially absorbed by molecules of porphyrin produced by the bacterium which works as photosensitizing agent by inducing the formation of cytotoxic molecular species.
