According to MayoClinic.com, headaches can be either primary or secondary. Primary headaches do not occur due to an underlying medical condition, but are rather caused by overactive pain receptors or chemical activity in the brain, or muscle tension in the head and neck. These headaches include migraines, tension headaches and cluster headaches, and can be hereditary. Secondary headaches, however, are symptoms of another underlying cause or disease, such as medication, tumors, blood vessel disease, infection or nerve damage.
Medications and Chemicals
Some prescription medications can cause headaches. Reading the information inserts that accompany new medication can help identify any possible side effects or contraindications. Overuse of pain medication can also be an underlying cause of headaches. Commonly referred to as "rebound headaches," headaches from pain medication occur as the body adapts to the medication, therefore the headache may worsen and cause an increased need for the medication or cause a headache when the medication has not been taken. According to MayoClinic.com, the way to stop rebound headaches is to gradually decrease or stop the medication altogether after consulting a physician. Alcohol, caffeine and exposure to chemicals can also cause secondary headaches.
Brain Tumors
MayoClinic.com defines a brain tumor as a "mass or growth of abnormal cells" in the brain. These growths can develop in the brain or spread to the brain from other body areas. They can be benign, meaning noncancerous, or malignant, meaning cancerous. These headaches are caused by the damage to surrounding tissue due to the tumor. Symptoms for this type of headache include those that gradually worsen in frequency and severity, are accompanied by nausea or vomiting, cause loss of movement or feeling in the arms or legs, dizziness, speech problems, confusion, vision problems, hearing problems or seizures. Cancers that can commonly spread to the brain are breast, colon, kidney, lung and melanoma.
Blood Vessel Disease
Strokes are disorders of the activity or formation of blood vessels, and can play a role in causing pathological headaches. There are two types of stroke, notes the National Institute of Neurological Disorders and Stroke: hemorrhagic and ischemic. A hemorrhagic stroke consists of a bursting, or ruptured, blood vessel, whereas an ischemic stroke involves the cessation of blood supply to the brain. Headaches from a hemorrhagic stroke occur suddenly and worsen with activity. The blood that fills the spaces in the brain after a ruptured blood vessel can cause serious and extensive damage. Cerebral aneurysms, or ballooning of arteries, can rupture and can be life-threatening. Headaches from ischemic stroke usually occur on the same side as the blockage, and pain can occur in the eye on the affected side.
Inflammation
Infections can cause inflammation in the brain and spinal cord, causing damage to nerve cells, brain tissue and blood vessels that leads to severe headaches and requires emergency attention, during which cerebro-spinal fluid is drawn in order to identify the microorganism causing the infection. Treatment consists of antibiotics, antifungal or antiviral medication, in addition to pain medication.
Trigeminal Neuralgia
Some severe headaches may be due to problems with the trigeminal nerve that controls sensations from the brain to the face and mouth. The main theory is that during trigeminal neuralgia, this nerve is constricted or compressed by surrounding blood vessels, presenting with symptoms that include a shocking sensation, stabbing pain or muscle spasms along with the headache. Pain can occur by merely touching the face. Surgical intervention as well as medication therapy may be indicated for treating this condition.
Considerations
Other pathological causes for headache can include injury, influenza, hangovers and eye disease. MayoClinic.com recommends immediate medical attention if a headache is sudden and severe, and is accompanied by fainting spells, dizziness, confusion, fever, numbness, stiff neck, vision trouble, speech problems or difficulty walking. Headaches that cause disruptions to everyday life but are not so severe require a physician consultation for treatment options.
