Background: Canine allergic dermatitis, including atopic dermatitis, often requires antibacterial therapy for concurrent infections. Oclacitinib is indicated for treatment of pruritus associated with allergic dermatitis and the clinical manifestations of atopic dermatitis in dogs aged ≥12 months.

Hypothesis/Objectives: We aimed to determine if there was a quantitative difference in antibacterial use by dogs with allergic dermatitis receiving oclacitinib vs. other anti-pruritic therapies and before vs. after oclacitinib.

Animals: In this retrospective case-control study, cases (n = 58) included dogs suffering from allergic dermatitis aged ≥12 months receiving oclacitinib and controls (n = 205) were counterpart dogs treated with other anti-pruritic therapies.

Methods: Clinical histories of dogs with allergic dermatitis were collected from a small animal university hospital. Multivariable logistic regression models were developed adjusting for underlying skin or ear conditions to determine whether cases were prescribed fewer antibacterials than controls.

Results: The odds of systemic antibacterial usage were lower in cases vs. controls [odds ratio (OR): 0.29 (95% confidence interval 0.12–0.71); P = 0.007]. The odds of amoxycillin clavulanic acid usage (12.5–25 mg/kg orally every 12 h) was lower in cases vs. controls [OR: 0.08 (0.01–0.71); P = 0.024]. Topical antibacterial drug use was reduced overall; however, only the odds of neomycin use was lower in cases vs. controls [OR: 0.3 (0.1–0.89); P = 0.029]. Cases had higher odds of experiencing improvements in allergic dermatitis categories vs. controls [OR: 7.89 (3.26–19.13); P < 0.001].

Conclusions and Clinical Importance: Our results suggest that use of oclacitinib to treat allergic dermatitis in dogs is associated with less antibacterial use than other anti-pruritic therapies.

背景：犬过敏性皮炎，包括特应性皮炎，通常需要对合并感染进行抗菌治疗。Oclacitinib适用于治疗≥12个月大的犬过敏性皮炎相关的瘙痒症和特应性皮炎的临床表现。

假设/目标： 我们的目的是确定接受oclacitinib与其他抗瘙痒疗法的犬相比，使用oclacitinib的过敏性皮炎犬的抗菌使用量是否存在定量差异。

动物： 在这项回顾性病例对照研究中，病例（ñ = 58）包括接受oclacitinib和对照组（≥12个月）过敏性皮炎的狗（ñ = 205）是用其他抗瘙痒疗法治疗的对犬。

方法：从一家小型动物大学医院收集了过敏性皮炎犬的临床病史。开发了多变量logistic回归模型，以针对潜在的皮肤或耳朵状况进行调整，以确定处方药是否比对照组少。

结果： 与对照组相比，全身使用抗菌药物的几率更低[几率（OR）：0.29（95％置信区间0.12-0.71）； P= 0.007]。与对照组相比，阿莫西林棒酸的用法（每12小时口服12.5-25 mg / kg）比对照组低[OR：0.08（0.01-0.71）;P= 0.024]。总体上减少了局部抗菌药物的使用；然而，与对照组相比，新霉素的使用几率更低[OR：0.3（0.1–0.89）；P= 0.029]。与对照组相比，变态反应性皮炎病例发生改善的几率更高[OR：7.89（3.26–19.13）；P <0.001]。

结论和临床重要性： 我们的结果表明，与其他抗瘙痒疗法相比，使用oclacitinib治疗犬过敏性皮炎的抗菌作用更少。