Some stings can cause an allergic reaction that doesn’t appear for a week or two or even longer. It can cause a rash, blisters, or other kinds of skin irritations.
Your healthcare provider can give you topical or oral treatments to address the condition.
A box jellyfish’s tentacles can leave permanent scars, including keloids, which are raised areas of scar tissue. There may be changes in skin color, and lichenification, in which the skin becomes thick and leathery in appearance. In some cases, areas of the skin die.