The present paper consists of a co-word analysis of the previous research in the medical spa field published in the Web Science Core Collection database. The study’s main purpose is to identify the past trends in the medical spa field from the tourist and medical perspectives and to anticipate the future research focuses in the field. In this regard, the article is based on four objectives that create a descriptive picture of the research in the medical spa area, such as (i) studying the current state of the art, (ii) analysing the most visible articles in the field, (iii) highlighting the leading research interests in medical spa research and (iv) anticipating new possible research trends that link cost-effective medical spa activity to COVID-19 post-recovery treatments. A total of 627 articles, published between 1997 and 2021 (March), were analysed, and the data were interpreted using the VOS Viewer software. The study results indicate that high interest in medical spas started to become observable in 2015, when the funding bodies became interested in this field and began supporting publishing and research regarding medical spas. The main subjects investigated in previous studies were related to the specific issues of the industry and tourism activity. They also considered the medical approach of the spa and the use of natural resources in treating different diseases. Except for these main interests, since 2020, it has started to become evident that another approach in the published studies may lead to a new trend in research. The study results show that researchers have begun to investigate the possibility of using medical spa resorts to aid post-COVID-19 recovery, which is considered a cost-efficient option for completing traditional treatment. This new focus in research proves that the medical spa field can rebrand itself as playing a supportive role in national healthcare systems in countries with a long tradition in balneotherapy, and gives a new developing trajectory to the medical spa industry.