Evidence that the immunopathogenic mechanism of lithium‐induced psoriasis differs from that of regular psoriasis

A relative resistance of T cells to dexamethasone in bipolar disorder

“…Bipolar disorder (BD) is a severe and chronic mood disorder with a complex and an unraveled pathophysiology (1). Several studies have reported on an activated immune system in BD, i.e., an activated T‐cell system (2–4), raised numbers of B cells (2), an activated monocyte/macrophage system (5–11), increased serum levels of acute phase proteins (12, 13) and a higher prevalence of thyroid, gastric and islet autoantibodies (14–17). The outcomes of these studies have led to the hypothesis that immune activation forms part of the etiopathogenetic mechanism leading to BD.…”

Lithium, Antipsychotics, and Risk of Psoriasis

“…7,13 Although various possible mechanisms have been described to explain how lithium may induce or exacerbate psoriasis, the exact mechanism is not known, and it has even been suggested that the mechanisms for regular and lithium-induced psoriasis may not be the same. 28,29 In a small interview-based study, the authors found a higher incidence of cutaneous reactions (only 2 cases with psoriasis) after exposure to lithium, but only in female patients. Furthermore, the only 2 patients in this study who developed psoriasis after exposure to lithium were older than 50 years.…”

The role of drugs in the induction and/or exacerbation of psoriasis

“…As with lithium, β‐blockers have been reported to aggravate psoriasis and induce psoriasiform rash, although in this instance, it has been questioned whether this is actually psoriasis 5 . However, psoriasis induced or worsened by the administration of beta‐blocking agents has been reported 6–10 …”