6810 Successful Insulin Allergy Desensitization To Humalog During The Second Trimester Of Pregnancy

Abstract Disclosure: J. Noreña: None. S. Seav: None. S. Jiang: None. S. McGhee: None. M. Tan: None. M. Basina: None. Background: Insulin allergy is rare, occurring in only 0.1 to 3% of people with insulin-treated diabetes. During pregnancy, this incidence is even lower due to a relative immunosuppressive state. Currently, there are no standardized insulin allergy desensitization protocols for this specific patient population. Clinical Case: A 39-year-old female (G4P3003) with T2DM and multiple prior medication allergies presented to the antepartum unit in her 17th week of pregnancy due to hyperglycemia and reported insulin allergy to NPH insulin.Patient was initially diagnosed with gestational diabetes during her third pregnancy, requiring NPH insulin which she seemed to tolerate well at the time. She remained medication-free for two years post-delivery but later developed T2DM with an A1c of 6.8%. Metformin and Jardiance, previously prescribed, were discontinued upon confirmation of her current pregnancy. She opted to manage her diabetes through diet and exercise alone, but her A1c rose to 7.0%, prompting the initiation of NPH.Following the first dose of NPH at home, she experienced a localized burning sensation at the injection site associated with facial flushing, followed by a diffuse, pruritic, erythematous rash on her face, chest, abdomen, and bilateral arms. Due to her history of anaphylaxis to other drugs (mainly antibiotics), she was admitted to the hospital for monitoring. Inpatient attempts with lower doses of NPH and then a trial of glargine triggered new rash episodes. Work-up revealed negative insulin antibodies, low IgG, and a normal CBC. She was started on Humalog to cover basal dose administered every 6 hours and additional prandial injections, which she tolerated prior to discharge. One week later, she developed a new local erythematous reaction at the Humalog injection site followed by a generalized rash which led to her readmission.Allergy was consulted and facilitated a successful desensitization protocol to Humalog. The protocol included escalating doses of insulin administered every 30 minutes (0.1u, 0.2u, 0.4u, 0.8u, 1u, 2u, 3u, 3u) to achieve a pre-determined cumulative dose of 10.5 units. Patient tolerated the protocol well and was discharged with q6h Humalog for basal coverage in addition to prandial doses with plan to transition to insulin pump therapy with Humalog soon. Conclusion: This unique case demonstrates how insulin desensitization can be a safe and successful strategy to help achieve insulin tolerance and glycemic control during pregnancy. Election of an insulin, such as Humalog, that can achieve the one-hour post-prandial glucose target during pregnancy and also provide effective basal coverage should be considered as desensitization can only be done with one insulin type at a time. Presentation: 6/2/2024