Does wearing someone's contacts hurt your eyes?

Each person has a unique eye shape and contact lenses are specifically fitted to an individual. If the contact lenses are too small, they will feel uncomfortable and tight and have the potential to rupture blood vessels in the eye or cause other, potentially serious, damage If they are too lose, they might fall out. Additionally, it is unlikely another person's prescription will work for you. Sharing lenses also increases the risk of spreading diseases. You have no way of knowing how hygienic someone else's lenses might be. If you need contacts, see an eye doctor and get a pair that are specifically made for you.