Her father said the 15-year-old suffered seizures and lost brain function after taking excessive doses of the allergy medicine.
ENID, Okla. — A 15-year-old Oklahoma girl died after reportedly taking part in the so-called Benadryl challenge, a dangerous social media trend involving excessive doses of an over-the-counter allergy medicine, according to her father.
Richard Presson confirmed his daughter Leah Presson’s death on June 26, two weeks after he first spoke publicly about her condition. He said Leah had suffered seizures and was placed on a ventilator in an intensive care unit after tests showed she had lost brain function. No autopsy report, toxicology findings or official determination of her cause and manner of death had been publicly released.
Presson said one of Leah’s friends told him the girls had taken part in the challenge, which involves consuming large amounts of diphenhydramine in an attempt to become intoxicated or experience hallucinations. The amount Leah reportedly took has not been disclosed, and the reported connection to the challenge rests largely on accounts provided by her father and the friend.
“Within 24 hours, she tried this, and she’s laying lifeless,” Presson said while his daughter remained hospitalized. He described watching her condition worsen as heartbreaking. He said Leah had been healthy before the incident and that the family initially thought her seizures might be connected to her history of asthma.
Diphenhydramine is the active ingredient in Benadryl and some generic allergy and cold medicines. The Food and Drug Administration warned in 2020 that taking more than the recommended dose can cause serious heart problems, seizures, coma or death. The agency issued the warning after receiving reports of teenagers being hospitalized or dying following participation in the online challenge.
The FDA has said diphenhydramine is safe and effective when used as directed. In excessive amounts, however, it can disrupt the heart’s rhythm and affect the brain and nervous system. Federal officials have urged consumers to follow product labels and store medications where children cannot easily reach them.
Presson said Leah had wanted to become known on social media and described her as a generous person with a contagious laugh. As doctors reported no brain activity, the family discussed donating her organs. Public reports did not provide confirmed details about whether a donation took place or how many recipients might have benefited.
The case renewed attention to the role of social media in spreading dangerous challenges. TikTok has said material promoting behavior that could cause serious injury violates its community rules and is removed. The company has also said searches connected to known dangerous challenges may direct users to safety information rather than videos promoting the activity.
YouTube has said its policies prohibit content that encourages dangerous challenges or substance misuse that could lead to serious injury or death. Publicly available reports did not establish which platform, if any, Leah used in connection with the reported incident.
Presson said he shared his daughter’s story to make other families aware of the risks posed by online trends. As of July 10, authorities had not publicly released investigative findings confirming the circumstances of Leah’s death. Any official medical examiner or toxicology report would provide the next significant update in the case.
Author note: Last updated July 10, 2026.