Guernsey's health department is urging all users or former users of a controversial cancer drug GcMAF to contact their GP.
The unlicenced drug has been banned after its UK factory closed amid fears materials used aren't fit for human consumption.
Hundreds of islanders have already pleaded with politicians and health officials to have the ban lifted.
Questions have been asked in Guernsey's States about GcMAF.
The Health Minister Deputy Paul Luxon says that banning the product was a 'natural follow-up' to MHRA concerns over the manufacturing process.
He was asked by Deputy Barry Paint about whether the GcMAF at the Border Agency had been tested, but the Minister didn't have an answer.
The weekend event coincides with International Pride Month and the 51st anniversary of the Stonewall riots.
The scheme has been backed by the island's Lieutenant-Governor, and is the first of its kind in the Channel Islands.
Sunny spells and isolated light showers. After dusk fair spells with isolated showers.