Sport Purple for Platelets Day is observed worldwide every last Friday of September. Launched by the Platelet Disorder Support Association (PDSA), this annual awareness campaign aims to highlight idiopathic thrombocytopenic purpura (ITP), an autoimmune disorder characterized by a low platelet count and an increased risk of bleeding. Participants are encouraged to wear purple, which symbolizes bravery and is associated with one of the disorder's symptoms—spontaneous bruises. Activities include painting nails, dyeing hair, lighting homes in purple, and organizing community events to promote understanding of ITP. Additionally, individuals can support the cause by donating to the PDSA or sharing information on social media using the hashtags #ITPAwareness and #PaintTheTownPurple.