Severe allergic reactions are typically associated with well-known culprits like peanuts, shellfish, or insect stings, yet life-threatening emergencies can stem from far more unexpected everyday items. At the 2026 Annual Scientific Meeting of the American College of Allergy, Asthma and Immunology (ACAAI), medical researchers highlighted three unusual pediatric cases of anaphylaxis—a dangerous, potentially life-threatening allergic reaction that requires immediate treatment with epinephrine. While the three cases involved completely different products, they share a vital lesson for doctors and patients alike: when an allergic emergency occurs without an obvious cause, the true trigger may be hiding in plain sight.
The most surprising of the three cases centered on a 15-year-old boy who experienced a medical emergency just minutes after trying a new energy drink. Almost immediately, he broke out in widespread hives, began wheezing, and struggled to breathe. Emergency room physicians administered two doses of epinephrine alongside albuterol, an antihistamine, and intravenous fluids before his symptoms resolved. A review of the beverage’s ingredient label revealed a surprising potential culprit: five grams of collagen derived from cod, a type of fish.
What made the teen’s case especially puzzling was his medical history and subsequent allergy testing. The boy, who had asthma, eczema, and allergic rhinitis, had previously experienced only mild lip swelling and throat itching after eating canned tuna, yet he could eat salmon without any problems. When allergists performed standard skin prick tests using commercial extracts of cod, tuna, and flounder, every result came back negative, despite his severe reaction following consumption of the collagen-containing drink.
“This case shows how tricky fish allergy can be,” explained study author and ACAAI member Annabelle Rowland, MD. “Collagen from fish is showing up in a growing number of products, from drinks to supplements. Standard fish allergy tests mostly look for a different fish protein and contain very little collagen, so a person can test negative and still react.”
The findings highlight a potential blind spot in conventional fish allergy testing. Commercial fish extracts contain relatively little collagen and primarily detect sensitization to other fish proteins, particularly parvalbumin. As a result, patients with collagen-specific allergies may receive negative results despite being at risk for severe reactions. Although the researchers suspected fish collagen was responsible for the teen’s anaphylaxis, the diagnosis remained provisional. His family was asked to provide fresh cod for additional prick-to-prick testing, but the results were still pending when the case was reported. Notably, the teen had not exercised or taken nonsteroidal anti-inflammatory drugs (NSAIDs) before the reaction, making those potential contributing factors less likely.
Alongside the energy drink case, researchers presented two other surprising potential triggers of severe allergic reactions in children. In one report, a 10-year-old girl with scalp eczema suffered her first severe allergic reaction after applying cold-pressed castor oil to her hair, despite having used heat-pressed castor oil safely for years. Subsequent skin prick testing was positive for the cold-pressed oil but negative for the heat-pressed version, supporting the researchers’ conclusion that processing methods played a critical role. Lead author Keyun Wang, DO, explained that while heat refining breaks down certain allergenic castor bean proteins, “cold pressing keeps certain castor bean proteins intact,” demonstrating that how a plant oil is processed can be just as important as its source.
In the third case, an 11-year-old girl suffered two separate anaphylactic episodes within a single week after handling popular squishy squeeze ball toys—first at home and later at school. Blood testing revealed previously unrecognized sensitization to latex, raising questions about whether latex contamination or cross-reactivity with materials in the toys could have contributed to her reactions. Although the precise trigger was not established, no alternative cause was identified. As case report lead author Megan Marte, MD, emphasized, “These toys are often marketed as non-toxic rubber, but they can contain a long list of chemical additives, and their exact makeup usually isn’t disclosed.”
Together, these three cases illustrate how hidden ingredients, manufacturing methods, and poorly characterized product materials can complicate the identification of serious allergic triggers. The energy drink case is particularly noteworthy because it demonstrates how conventional allergy testing may fail to detect sensitivity to less commonly tested proteins, potentially leaving patients unaware of important risks. For consumers, especially those with existing allergic conditions, checking ingredient labels and recognizing the warning signs of anaphylaxis remain essential. Anyone experiencing symptoms of a severe allergic reaction should receive prompt epinephrine treatment and emergency medical care. When the cause remains unclear, consultation with a board-certified allergist can help uncover less obvious triggers and guide appropriate testing to reduce the risk of future reactions.
