The development of intelligent healthcare support systems always requires a formalization of medical knowledge. Domain ontologies are especially suitable for this purpose but their construction is, in most cases, manually addressed. This results in long and tedious development processes that hamper their real applicability. This is why there is a need of ontology learning methods that aid the ontology construction process. Considering the enormous amount of medical knowledge available freely on the Web, one may consider it as a valid source for developing knowledge acquisition systems. In this paper we offer an overview of an automatic and unsupervised method for learning domain ontologies from the Web. We also introduce its application over a specific medical domain in the frame of the K4Care European project.