When a subconjunctival hemorrhage, which is the medical term for blood in the eye, occurs, artificial tears can be applied to soothe the eye, but there is nothing that can help repair the broken blood vessels, according to All About Vision. The hemorrhage will heal on its own, dissipating in 7 to 10 days. It is also important not to rub the eye as this can cause it to re-bleed, in much the same way as a nosebleed will start to bleed again if touched.
Subconjunctival hemorrhages happen when small blood vessels break beneath the white of the eye, causing redness. This can happen for several reasons including a sudden increase in blood pressure due to lifting something heavy, constipation, laughing or sneezing; taking blood thinners such as warfarin or aspirin, a blood clotting disorder or a vitamin K deficiency.
Usually, despite the alarming appearance, subconjunctival hemorrhages do not interfere with vision and may not even be significantly uncomfortable. However, it is always a good idea to see an eye care professional, especially if the redness is persistent or unusual and if there is any kind of discharge from the eye. These symptoms can be an indication of a more serious condition, such as a bacterial infection or glaucoma.