Between 5 and 49% of patients undergoing methadone maintenance treatment (MMT) consume alcohol. They show less willingness to comply with treatment and are less committed, their treatment times are longer, and their observance is weaker. Alcohol misuse is the main cause of their increased mortality and morbidity rates. We conducted a multivariate, prospective, open-label study in two groups of methadone patients: the first suffered from alcohol use disorder according to the criteria of the alcohol use disorder test (AUDIT), while the second was alcohol-abstinent. In the process, we completed evaluations on the Toronto alexithymia scale, together with a self-esteem inventory and a temperament and character inventory (TCI-R). Our study included 152 patients, 27.6% of whom were high-risk consumers. Comparison of the alcohol high-risk consumers group and the low-risk consumers showed that the former had higher rates of alexithymia, weaker self-esteem, and lower scores of self-directedness.