Background: Intravenous nutrient therapies (IVNTs) have gained popularity on the commercial market. Targeted at people with a variety of ailments and needs, the procedures allegedly offer numerous benefits and quick results, widely advertised on the websites of drip bars and health clinics as well as in the available literature. What is less often presented is the point of view of the customers of such services and the opinions of health personnel. Although the latter perspective seems to be crucial, little is known about it. Therefore, the purpose of this study was to present the opinions and experiences of health professionals (n = 188) on commercially available IVNTs dedicated to adults. Methods: The study was conducted between April 2019 and March 2020 by means of a survey using an ad hoc questionnaire made available mainly to health professionals attending public health postgraduate courses at the Poznan University of Medical Sciences, Poland. Results: As many as 91.5% of the respondents had heard of commercially available IVNTs (mostly from the media), and 47.3% knew of a facility offering such services. Among the possible situations where the use of IVNTs would be justified, the most commonly mentioned was a diagnosed nutrient deficiency (37.8%), while the least common ones were libido problems (1.1%) and the need to speed up metabolism (2.1%). For 25.5% of the respondents, there was no good rationale for using IVNTs. As many as 15.4% had no opinion on the subject. Health risks of IVNTs were recognised by 95.2% of professionals, with the biggest concerns being the lack of full information on patients’ health status and medical contraindications (84%), the risk of overdose and interactions (77.1%), and hypersensitivity or allergic reactions (75.5%). Among the reasons for IVNTs’ popularity, the respondents listed not only fads spread by celebrities and social media (89.4%) and the need for quick, effortless remedies (77.1%), but also reasons inherent in the Polish healthcare system. As many as 80.3% of the respondents stressed the need for public health institutions to take a stand on commercial IVNTs. Knowing of an IVNT facility was not significantly associated with the opinions of professionals in key areas. Conclusion: Postgraduate public health courses are a good opportunity to engage health professionals in discussions about the current challenges, trends, and needs in the area of health promotion and healthcare. This study’s findings shed some light on the opinions about IVNTs held by health professionals, who are important stakeholders of the healthcare system. Thus, these findings may help to better understand the popularity of IVNTs and incorporate health professionals’ perspectives in future efforts aiming to increase the awareness of IVNT-related health risks among both professionals and patients.