Those participating in launch themselves from the rear of a boat and into the wake behind it, as the boat continues to move. Officials in Alabama have said it has claimed the lives of four people.
Jacob Stevens, from Ohio, died on April 12 after overdosing on Benadryl as part of the social media challenge. He was filmed by his friends downing an alarming number of the anti-allergy pills.
The Benadryl Challenge trend, which has already killed two US teens, sees people swallow multiple antihistamines tablets before posting videos of their experience.
The Benadryl Challenge is the latest potentially fatal craze to hit TikTok s algorithm, encouraging users to swallow a dangerous amount of antihistamine medication.
Healthcare workers are issuing warnings about the challenge, which encourages people to take a dozen or more Benadryl pills at one time as TikTok says its never seen this type of content trend.