“…For example, certain odors (e.g., peppermint oil) may alter the endogenous opioid pathways of the brain and therefore reduce pain or anxiety (Bushnell, Ceko, & Low, 2013;Ching, 1999;Villemure, Slotnick, & Bushnell, 2003). Other odors (e.g., eucalyptus or thyme) have remarkable antibacterial, antifungal, anti-inflammatory, immunomodulatory, or antioxidant effects (Brochot, Guilbot, Haddioui, & Roques, 2017;Caceres et al, 2017;Divband, Shokr, & Khosravi, 2017;Hans, Grover, Deswal, & Agarwal, 2016;Jaradat, Adwan, K'aibni, Shraim, & Zaid, 2016;Kenia, Hoghton, & Beardsmore, 2008;Schönknecht, Krauss, Jambor, & Fal, 2016;Zhou et al, 2016). Recent meta-analyses and systematic reviews support the notion that aromatherapy may exert clinical symptom relief when compared with placebo or standard treatment.…”