A subconjunctival hemorrhage can have a clear trigger or appear without any obvious reason. Knowing the most common causes helps you understand your own situation and take steps to protect your eye health going forward.
Sudden Increases in Pressure
A strong, abrupt physical action can temporarily raise pressure in the veins of the head, putting stress on the small, fragile blood vessels of the eye. Forceful coughing, hard sneezing, vomiting, or straining during heavy lifting are all common triggers.
Minor Eye Trauma
Even a relatively gentle impact or irritation can cause a vessel to break. Vigorous eye rubbing, an uncomfortable contact lens, or a minor bump to the eye area are all possible causes. You do not have to experience a significant injury for a hemorrhage to occur.
Underlying Health Conditions
Certain systemic conditions can weaken the walls of blood vessels or interfere with normal clotting, making a hemorrhage more likely. High blood pressure (hypertension) and diabetes are among the most common health factors associated with recurrent or unexplained cases. If you have either condition, managing it carefully with your primary care provider is important for your overall eye health.
Blood-Thinning Medications
Medications that reduce the blood's ability to clot can make bleeding easier to trigger, even from a very minor event. Common examples include aspirin, warfarin, clopidogrel, and newer anticoagulant medications. If you take any of these, a subconjunctival hemorrhage may occur more readily than it would otherwise.
No Identifiable Cause
In many instances, a subconjunctival hemorrhage develops without any clear trigger. These are called idiopathic cases, meaning no specific cause can be found. For otherwise healthy individuals, an isolated spontaneous hemorrhage is generally not a cause for concern, though recurrent episodes should be discussed with your eye doctor.
