Stem cell exosome therapy has shown significant potential in treating hair loss, but its safety profile has not been thoroughly studied. This paper reported a case of a 32-year-old female patient who experienced an allergic reaction following adipose-derived stem cell exosomes injection for hair loss treatment at the Plastic Surgery Hospital, Chinese Academy of Medical Sciences in June 2023. Within 24 hours post-injection, the patient developed swelling of the forehead and right postauricular lymph nodes, accompanied by mild pain, and left posterior ear lymph nodes 48 hours later. Ultrasound examination revealed thickening of the local soft tissue and enlarged lymph nodes. The condition was diagnosed as an injection-induced allergic reaction. The symptoms gradually subsided after combined treatment with lidocaine, 5-fluorouracil, and triamcinolone acetonide injections. During a 6-month follow-up period, the patient did not experience any recurrence of allergic reactions, and the therapeutic effects remained stable. This case report highlights the potential risk of allergic reactions associated with stem cell exosome therapy for hair loss, underscoring the need for close monitoring and timely intervention in clinical applications to ensure both safety and efficacy.

Stem cell exosome therapy has shown significant potential in treating hair loss, but its safety profile has not been thoroughly studied. This paper reported a case of a 32-year-old female patient who experienced an allergic reaction following adipose-derived stem cell exosomes injection for hair loss treatment at the Plastic Surgery Hospital, Chinese Academy of Medical Sciences in June 2023. Within 24 hours post-injection, the patient developed swelling of the forehead and right postauricular lymph nodes, accompanied by mild pain, and left posterior ear lymph nodes 48 hours later. Ultrasound examination revealed thickening of the local soft tissue and enlarged lymph nodes. The condition was diagnosed as an injection-induced allergic reaction. The symptoms gradually subsided after combined treatment with lidocaine, 5-fluorouracil, and triamcinolone acetonide injections. During a 6-month follow-up period, the patient did not experience any recurrence of allergic reactions, and the therapeutic effects remained stable. This case report highlights the potential risk of allergic reactions associated with stem cell exosome therapy for hair loss, underscoring the need for close monitoring and timely intervention in clinical applications to ensure both safety and efficacy.