Panda and Clifford are having a fun time together when Clifford realizes Panda is using him to get close to his sister, Lucy. While running away from Panda, Clifford accidentally gets peanut butter all over himself, and he experiences a severe allergic reaction, causing his face to swell and his breathing to slow. Panda looks for the allergy pen to save Clifford and experiences a similar allergic reaction. Despite his condition, he manages to save Clifford, who in turn saves him with another allergy pen.
Ed plays with bunnies and starts sneezing, itching, and exhibiting other strange symptoms, some of which are unrealistic. Double D diagnoses Ed with an allergy to rabbits. They attempt to treat his allergy with cold cream and talcum powder.
Beakman explains what allergies and allergens are. He talks about how the immune system causes the allergic reactions through the production of histamines. He uses a clip to show how a sneeze happens physiologically.