Background: Sociodemographic characteristics and inflammatory cytokines, such as interleukin (IL)-1β, IL-1 cytokine receptor type 2 (IL1R2), IL-6, and triggering receptor expressed on myeloid cells like 2 (TREML2), may influence psychological disorders, including discomfort. Single-nucleotide variants (SNVs) determine individual differences for the modulation of cytokines and indicate that genetics may also influence the comfort levels. However, the relationship between sociodemographic characteristics, holistic comfort, and the roles played by IL1B rs16944, IL1R2 rs4141134, IL6 rs1800795, and TREML2 rs3747742 SNVs on the comfort levels of family caregivers (FCGs) of head and neck cancer (HNC) patients in palliative care (PC) is unknown. Thus, its investigation consisted in the aim of the present study. Methods: A questionnaire was applied to obtain sociodemographic information on 95 FCGs. The genotypes were identified using TaqMan assays. The Holistic Comfort Questionnaire for the Caregiver, which consists of 49 questions, was used to measure comfort levels. Differences between groups were assessed by the t test and linear regression. Results: Employed FCGs ( p = .04), those youngest ( p = .04), smokers ( p = .04), and those with IL1R2 GA or AA genotypes ( p = .03) presented lower comfort regarding the overall, environmental, sociocultural, and psychospiritual domains, respectively. Conclusions: Employment status, smoking habit, young age, and SNV IL1R2 rs4141134 could influence the comfort levels of FCGs of patients with HNC in PC.