Substance use disorders and chronic itch

In vitro atlas of dorsal spinal interneurons reveals Wnt signaling as a critical regulator of progenitor expansion

“…Finally, we also found enriched terms in the dI clusters related to different drug addiction pathways, including amphetamine and endocannabinoids for dI1/dI2s, and amphetamine, morphine, and cocaine for dI4/dI5s (Figures 2G and S3A; Table S2). Such signatures suggest the dIs mediate the ability of psychoactive drugs to modulate pain and itch perception (Lipman and Yosipovitch, 2021) or proprioception (Downey et al, 2017). Other dI-subtype markers identified in this analysis include receptors, ion channels, and adhesion molecules (Figures S3A and S3B; Table S4).…”

A protracted, postherpetic neuralgic ulcer treated with risperidone and intranasal butorphanol

“…Simultaneous activation of the κ-opioid receptor system and inhibition of the μ-opioid receptor system within the mesolimbic circuit act to decrease dopaminergic activity, resulting in an “antireward” effect on addiction and itching behavior. 10 Therefore, the successful use of these medications, along with the worsening of pruritus that occurred following treatment with oxycodone, a μ-opioid receptor agonist, may represent a central component of PHN pathogenesis that drives both pruritus and scratching behavior.…”

Psychiatric comorbidities in dermatitis artefacta: A systematic review and meta-analysis

“…Patients with substance use disorders also have altered pain sensitivity and sensory responsiveness, which may also be relevant to the self-infliction of superficial lesions; these patients sometimes exhibit other, possibly related dermatological phenomena, such as unexplained chronic pruritus. [53,54] A "final common pathway" that may link alterations in pain perception and response to the "psychic pain" is altered functioning of endogenous opioid receptors in the brain, though the exact receptors and pathways involved remain unclear. [55,56] In addition, certain substance use disorders, such as alcoholism, are genetically linked to depression; [45] in these cases, mechanisms similar to those described above for the "anxiety-depressive spectrum" may be relevant.…”