The headache and eye pain on the right side of the patient may be caused by the following reasons: 1. If the patient has an intensive attack of headache for a period of time, the patient has pain in one eye, accompanied by bulbar conjunctival congestion or double vision, tearing and nasal congestion, it is considered to be caused by cluster headache. 2. The headache and eye pain on the right side of the patient may also be caused by glaucoma, and it is recommended that the patient take the intraocular pressure to clarify, and the patient may also have blurred vision and decreased visual acuity. 3. If the patient has a history of migraine and the attack is similar to this one, the patient also has a right headache with mild eye swelling and pain, which may be caused by a migraine attack, the patient should not be too nervous and can take oral pain medication to relieve the symptoms.