Dexchlorpheniramine Maleate

The advent of biol. drugs in the past decade has significantly improved the treatment of several dermatol. diseases.These are commonly attributed to the active ingredient; however, the real culprit is often not disclosed. Patch testing, skin prick testing (SPT), and intradermal testing (IDT) have focused not only on the active ingredient but also on key excipients, such as polysorbate 80-present in the vehicle of many biologics, including secukinumab.A 40-yr-old woman with a history of hidradenitis suppurativa, who developed a paradoxical palmo-plantar psoriasis due to adalimumab, presented with a 4-mo history of injectionsite reactions to secukinumab 300 mg (Cosentyx).From the first administration, she developed extensive, well-defined erythematous-edematous itchy hives at the injection site, which started within an hour of administration and spontaneously resolved within 6 h.However, SPT with polysorbate 80 at 1:100 and 1:1000 dilutions, along with IDT using the same dilutions of polysorbate 80, and undiluted Cosentyx, yielded pos. results at 60 min.With reactivity to such high dilutions, a diagnosis of immediate reaction type contact urticaria due to polysorbate 80 was established.The drug was maintained, as all available biologics contain polysorbates, with the administration of 2 mg of oral dexchlorpheniramine the night before and 1 h prior to drug injection.A second-generation anti-H1 was considered, but dexchlorpheniramine was maintained due to good tolerance and patient′s preferences. This anti-H1 therapy was partially effective, reducing the size and duration of the injection-site wheals, and preventing the appearance of generalised wheals.When facing hypersensitivity reactions to biologics, excipients should be carefully considered, especially in cases of unclear origin and atypical clin. presentation. Since stages 3 and 4 of contact urticaria syndrome involve extracutaneous manifestations and potentially fatal anaphylactoid reactions to polysorbate 80 have been documented it may be necessary to identify hypersensitivity to this ubiquitous component.

Histamine H1 receptor (H1R) antagonists are widely used to treat allergic reactions; however, their effects on the central nervous system can impair motor functions. This study investigated the impact of first-generation (diphenhydramine and d -chlorpheniramine) and second-generation (epinastine, ketotifen, bepotastine, and levocetirizine) H1R antagonists on motor functions in mice using activity wheel, balance beam, inclined screen, and rotarod tests. First-generation H1R antagonists significantly impaired motor functions, with diphenhydramine exerting stronger effects than those of d -chlorpheniramine. Among the second-generation agents, bepotastine and levocetirizine had minimal effects on all motor functions, whereas epinastine and ketotifen suppressed spontaneous movement, similar to first-generation H1R antagonists but had little effects on balance, postural stability, and coordinated movement. These findings provide valuable insights into the differential effects of first- and second-generation H1R antagonists on motor functions. These results highlight the importance of understanding individual profiles of H1R antagonists to minimize adverse effects, ensure patient safety, and improve quality of life.