What could cause a headache on one side of my head and eye, and how can it be relieved?

One possible reason for repeated headaches on one side of the head and pain behind the eye is cluster headaches. These can be very painful and tend to happen in cycles or 'clusters'. Symptoms can be triggered by alcohol or tobacco use. Various treatments can relieve cluster headaches. More information about cluster headaches and treatments is available at https://www.brainandlife.org/disorders/headache.

If the headache and eye pain are new and severe, an important possibility to consider acute angle-closure glaucoma, which requires emergency treatment in a hospital in order to prevent blindness or other vision loss. Other symptoms of acute angle-closure glaucoma include blurry vision and seeing rainbows or halos. More information about acute angle-closure glaucoma can be found at https://www.aao.org/eye-health/diseases/what-is-glaucoma.

Other health conditions can also cause headache and eye pain. The appropriate treatment to relieve these symptoms depends on the exact cause of this pain, so it is important to seek help from a healthcare professional for a personalized medical assessment and treatment plan.