The analyses confirmed our three working hypotheses. First, academic pressure was indeed related to psychotropic drug use. The descriptive results in Table 1 showed that psychotropic drug users had more negative feelings about how well their studies were going than non-users. Moreover, even after controlling for other risk factors (Table 9), academic failure remained a highly significant factor. This findings is in line with what has already been established in the literature, whether at high school [30, 31] or university level [32]. This implies that, in addition to the usual prevention campaigns, additional measures should be proposed in order to limit the use of psychotropic drugs, both by better explaining their harmful consequences and by improving the well-being of student so that they no longer need to resort to them.

Our second hypothesis concerned the frequency of psychotropic drug use, namely regular or experimental. The results in Table 2 showed that for all the psychotropic drugs considered, use could vary from one student to another with some using drugs regularly (antidepressants, and psychostimulants in particular) and others much more occasionally (tranquilizers and hypnotics in particular). This contrasts with the use of psychotropic substances, which was mainly irregular (Table 3). This regular use confirmed the fact that some students were using psychotropic drugs for treatment purposes, as most classes of psychotropic drugs require daily dosing rather than sporadic use, indicating a medical regimen rather than recreational intent. In fact, 73.1% of psychotropic drug users reported that they had used them as part of a medical treatment. It is therefore highly plausible that the use of such drugs was often initiated by a prescription based on a medical diagnosis. However, steps must be taken to ensure that drug use that begins under medical supervision does not continue unchecked. This is in line with the findings of a literature review which suggests that one in three students prescribed a psychotropic drug subsequently diverts its use to other purposes [11].

Finally, our third hypothesis examined the differences in perceptions between users and non-users of psychoactive drugs. The results in Table 7 tended to show that the reasons for using psychotropic drugs as imagined by non-users differed considerably from those given by users. As mentioned above, the main reason given by users was that it was part of a medical treatment. None of the other reasons given reached 50% agreement, the most common being the need to reduce anxiety and stress in everyday life (45.5%). Conversely, non-consumers believed that this last reason was true for 80.4% of consumers, followed by study stress related (76.0%) and the desire to improve academic performance (65.8%). Although it is possible that the users may have consciously or unconsciously concealed some of their motivations for using, the systematic aspect of the differences recorded between users and non-users cannot be attributed to chance alone, and we can hypothesize that a certain amount of fantasy surrounds the use of these drugs. Directly related to this, our analyses also showed that non-users were more concerned about the possible negative effects (e.g. side effects, dependence, …) of psychotropic drug use than users themselves (Table 8). This difference may be due to various factors, such as a lack of knowledge about these drugs and their medical follow-up by the non-users, but also to a more or less conscious minimization of the negative effects by the users, who preferred to keep only the positive effects of these medications, perhaps in order to be able to continue their treatment, whether prescribed by a doctor or not. Our findings can be linked to a study showing that strategies for controlling one’s own drug use, and perceptions of such strategies, can vary widely between users and non-users [33]. We can also cite another study showing that the general population tends to overestimate the prevalence of substance use and underestimate the chances of stopping it [34]. It follows that it is necessary to strike a fair balance between the a priori attitudes that may exist towards users of psychotropic products and the reality and conditions of their use.

Psychotropic products include not only drugs but also illicit substances such as cannabis, cocaine or hallucinogens. As the use of such substances is more common than the use of psychotropic drugs, and as a significant proportion of the drug users in our sample also used substances, it was logical to include them in our analyses as well. The results showed that, unlike drugs, substances were almost never used on a regular basis (at least several times a week), suggesting essentially recreational rather than therapeutic use. However, we found that the use of cocaine, amphetamines and opiates was more frequent, although not regular, among users of psychotropic drugs than among non-users of these drugs. We can hypothesize either that the use of psychotropic drugs tends to normalize the use of psychotropic drugs in general, or that, in the absence of drugs, there is a substitution effect with other substances. On the other hand, the comparison between substance users, psychotropic drug users and non-users showed that substance users who did not use drugs had very similar characteristics to non-users. In particular, their health was generally very good, they were satisfied with their lives and they had few problems with their studies. This is consisted with what has previously been found in relation to cannabis [35]. The only real difference between substance users and non-users was that substance users took more risks than non-users. In contrast, students who used psychotropic drugs, whether or not in combination with psychotropic substances, generally did worse than the other two groups of students.

The proportions of psychotropic substance and drug users found in our study are similar to those observed in a study conducted in France among pharmacy students, although in the latter case only the use in the previous 3 months was considered [36]. In contrast, another study conducted in Brazil among pharmacy students found a much higher percentage of over-the-counter use of psychotropic drugs (79.2%) [37]. However, these were students attending evening classes and were on average older than the respondents in our own sample, and it is known that psychotropic drug abuse tends to increase with age [38, 39]. Compared with the total sample, women were more likely to be non-users of psychotropic substances or users of psychotropic drugs only, whereas men were more likely to be users of psychotropic substances, in combination or not with psychotropic drugs.

Although 71% of psychotropic substance users reported that at least some of these drugs were taken as part of a medical treatment, many other reasons for self-medication were reported by respondents. This must be related to the means of obtaining these drugs. Again, over 70% of consumers reported legal supply as part of a medical treatment, but many other sources were also reported, including family, friends, and purchases from pharmacies and the Internet. This is consistent with the existing literature, which highlights the variety of methods used to obtain psychotropic drugs, including theft [12]. On the other hand, it may be at odds with what De Souza et al. found with American students, for whom access to psychotropic drugs seemed to come mainly from friends who were already using them, rather than from health professionals [40]. Moreover, even if many psychotropic drugs are used as part of a medical treatment, this does not eliminate all risks. In fact, a study conducted in the United States showed that even within a treatment regimen, the dosage was not always adhered to, with frequent cases of over- or under-dosing [41], as is also the case, for example, in people with epilepsy who are being treated [42].

The context of psychotropic use may also differ between drugs or substances. As reported by McCabe et al., psychotropic substances are more likely used in a festive context in the presence of others, whereas psychotropic drugs are much more likely to be used when people are alone [43]. This is partly reflected in our study, since recreational use or use to facilitate social integration of psychotropic drugs was reported by only a minority of users, contrary to the opinion of non-users. When users of psychoactive drugs discussed their use with others, it was more likely to be with health professionals, friends or family members than with other students. This may be due to the private nature of drug use in the context of illness and treatment, but it may also be due to the fact that discussions with other students generally did not change the users’ own opinions (Table 6). The fear of being judged negatively, although not felt by everyone, may also have played a role.

This article presents data on the use of psychotropic drugs by students at the University of Lausanne. It is original because, in addition to the consumption itself, it also provides information on the feelings of users and non-users regarding the fact of consumption. The main limitation of this research is that it is based on a convenience sample that does not claim to represent all students at the University of Lausanne, nor university students in general. This means that it is not possible to generalize the results directly, either to all students at the University of Lausanne or to other populations. This must be clearly stated when referring to our results. In addition, the cross-sectional nature of the study makes it impossible to establish a causal link. Another important limitation is directly related to the choice of questions included in the study. The literature has shown that there are strong associations between the (poly-)use of illicit and licit substances, but we did not have information on the use of alcohol and tobacco products by the respondents in our survey. Our study is therefore unfortunately incomplete in this respect. In order to address the above limitations, a new study with a more comprehensive questionnaire and longitudinal data collection should be conducted. However, despite these various limitations, our analyses allow us to highlight interesting differences between users and non-users of psychotropic drugs, and to compare the opinions of these two groups.

Our results show that Switzerland, like other countries, is affected by the phenomenon of psychotropic drug use by students outside medical treatment. Belonging to the most educated part of the population is not a protective factor, and specific research into the causes of substance use among students should be explored, for example through qualitative research, to find out more about the processes involved for this specific population (i.e. academic pressure, our first hypothesis, and the context of use and frequency, our second hypothesis). Mamat et al. [11] have clearly shown that the use of illicit psychotropic drugs is increasing worldwide, and although we lack specific data for Switzerland, other recent studies confirm the magnitude of the problem [24, 44–46]. This steady increase is an indicator that the problem is far from being under control. In Switzerland, we can speculate that this may be related to a lack of coordination between health care actors. For example, we have no record of all the prevention campaigns that have been carried out over the last 20 years, although we know that many campaigns have been carried out at city, cantonal and federal level, targeting various legal and illegal substances. The lack of such a register makes it difficult to assess the relative merits and effectiveness of different types of prevention campaigns.

In line with public health recommendations [47], health professionals should also be better trained to recognize problematic situations in the student population in order to prevent drug and substance abuse from getting out of control. Furthermore, as shown by the results related to our third hypothesis (perception of users and non-users), better information could be provided to students when they enter university to remind them of the dangers of taking psychotropic products outside medical supervision. In this regard, we can hypothesize that the fact that more and more people are receiving prescriptions for psychotropic drugs [48, 49] could exacerbate illegal use by allowing greater access to drugs and greater familiarity with the whole family of products. Therefore, the difference between legal and illegal use in terms of consequences should be emphasized. Finally, students should be better informed about the health services to which they should turn if they have a problem.