There are two types of headaches that may cause pain on the right side of the head, a hemicrania continua headache and chronic migraine, according to Mayo Clinic. Both of these headache types may affect the right or left side of the head, but not both.
Hemicrania continua headache symptoms include pain on one side of the head, continuous pain and have spikes of severe pain, explains Mayo Clinic. A hemicrania continua headache may also occur alongside migraine symptoms and cause nasal congestion, tearing or redness in the eye and drooping of the eyelid or pupil constriction.
Chronic migraine may also cause pain on the right side of the head, claims Mayo Clinic. Chronic migraines occur at least 15 days or more each month for more than three months. These headaches cause a throbbing or pulsing sensation, and the pain is described as moderate to severe. A person may also notice that the headache is aggravated by physical activity. Nausea and vomiting may occur, and many people also report sensitivity to both sound and light.
Tension headaches are the most common type of headache, although they are usually not serious. Like migraines, the causes of tension headaches are unclear, although it is believed that they are brought on by some kind of change in brain chemistry, stress, depression, hunger and muscle strain. This type of headache is characterized by a constant pressure on the side of the head, or aching in the temples, back of the neck or head, states WebMD.
Cluster headaches tend to occur in cyclical patterns or clusters without warning and can last for several weeks. While the cause remains unknown as of 2015, it is believed that an abnormality of the hypothalamus and the body's biological clock are involved, due to the cyclical nature of attacks, explains Mayo Clinic.
It is common to have occasional headaches, but if someone has more than two or more headaches a week, he should see a doctor, states Mayo Clinic. If a headache causes severe pain, comes upon suddenly or occurs following an injury, emergency medical treatment may be necessary. Because of the many possible causes of a headache, it is critical for patients seeking treatment for a headache to provide as much additional information as possible when describing the symptoms and their recent history to their doctor to aid in diagnosis. While most headaches are not life-threatening, some unilateral headaches can be signs of severe trauma or disease, especially if this is the first time this kind of headache has occurred.