D3.264 - Delayed Type Hypersensitivity Injection Site Reaction Induced By Liraglutide

Liraglutide, a glucagon-like peptide-1 (GLP-1) receptor agonist, is widely used in the treatment of obesity and type 2 diabetes mellitus. Although its safety profile is generally favorable, an increasing number of cutaneous adverse reactions have been reported. However, hypersensitivity reactions to liraglutide remain insufficiently characterized.

This paper aims to describe the clinical features, diagnostic approach, management, and clinical implications of cutaneous hypersensitivity reactions associated with liraglutide therapy.

Clinical and paraclinical data from a patient presenting with a localized cutaneous reaction resistant to antihistamine therapy during liraglutide treatment were analyzed. In addition, a review of the literature regarding liraglutide-induced cutaneous hypersensitivity reactions was performed.

A 22-year-old Caucasian female with obesity (body mass index 30 kg/m²) presented with a 4-week history of pruritic erythematous lesions localized to the anterior abdominal wall. She was receiving subcutaneous liraglutide, titrated up to a daily dose of 3 mg. Following dose escalation, erythematous plaques developed at the injection sites approximately 24 hours after administration. Pruritus was mild, and treatment was continued. Clinical examination revealed well-demarcated, round erythematous plaques corresponding to injection sites. The patient reported a previous episode of acute urticaria at the age of 18 years.Patch testing with liraglutide (6 mg/mL, aqueous solution and petrolatum) showed mild positive reactions at 72 hours. Skin prick testing was negative. Intradermal testing with liraglutide diluted 1:10 in saline was negative at 20 minutes but positive at the 24-hour reading. Based on the clinical presentation and allergological testing, a diagnosis of delayed-type hypersensitivity reaction to liraglutide was established. Symptomatic treatment with topical methylprednisolone aceponate 0,1% was administered twice daily for two weeks, followed by once-daily application for 30 days, with continuation of liraglutide therapy.

Cutaneous adverse reactions to liraglutide range from localized injection-site reactions to extensive inflammatory eruptions. While injection-site reactions are known adverse effects, the distinction between immediate and delayed hypersensitivity reactions is not clearly defined in current product information. Increased awareness and appropriate diagnostic evaluation are essential to ensure safe long-term treatment.