The present invention provides a swallowable capsule suitable for providing phototherapy to a region of a patient's gastrointestinal (GI) tract, the capsule comprising one or more light sources emitting in the visible and/or NIR ranges and optical elements for shaping the light beam produced by said light sources, such that said light source(s) and said optical elements are capable of delivering an effective therapeutic dose to a target site within the GI tract. The present invention further provides a method for intraluminal phototherapy of the gastrointestinal tract using a swallowable capsule as described hereinabove.