  Errors in medication intake among elderly people are very common. One of the
main causes for this is their loss of ability to retain information. The high
amount of medicine intake required by the advanced age is another limiting
factor. Thence, the design of an interactive aid system, preferably using
natural language, to help the older population with medication is in demand. A
chatbot based on a subtractive cluster algorithm, included in unsupervised
learned models, is the chosen solution since the processing of natural
languages is a necessary step in view to construct a chatbot able to answer
questions that older people may pose upon themselves concerning a particular
drug. In this work, the subtractive mountain clustering algorithm has been
adapted to the problem of natural languages processing. This algorithm version
allows for the association of a set of words into clusters. After finding the
centre of every cluster -- the most relevant word, all the others are
aggregated according to a defined metric adapted to the language processing
realm. All the relevant stored information is processed, as well as the
questions, by the algorithm. The correct processing of the text enables the
chatbot to produce answers that relate to the posed queries. To validate the
method, we use the package insert of a drug as the available information and
formulate associated questions.
