Must read: 57 causes of Migraine(Headache) - 57 sickness headaches can lead to.

Many people underate headaches -  am also guilty of this. But it shouldnt taken as so. Headache, also called migraine can lead to some sicknesses, I mean dangerous ones, Sicknesses such as ebola, blindness etc as stated below.
Why I think headache is underestimated is because.
Headache might just come to be as a result of stress, lack of sleep and other petty diseases even though they kill. God helping, after sleeping or resting, you are relieved of the most common disease symptom, headache. But no beloved, it shouldn't be taken lightly or referred to as petty, the below diseases are diseases of which it's primary symptom is headache. So whenever you have an headache, rest and sleep, then if you aren't relieved, you should see a doctor.
- Common Cold
- Dehydration
- Influenza (Flu)
- Gastroenteritis (Stomach Flu)
- Menstrual Period
- Early Pregnancy
- Concussion
- Premenstrual Syndrome (PMS)
- Food Allergies
- Labyrinthitis
- Migraine
- Food Poisoning
- Alcohol Withdrawal Delirium
- Strep Throat
- Assess your child's symptoms »
- Scarlet Fever
- Anxiety Disorder
- Diabetic Ketoacidosis
- Fifth Disease
- Giardiasis
- Tonsillitis
- Extremely High Blood Pressure
- Endometriosis
- West Nile Virus Infection (West Nile Fever)
- Glaucoma
- Malignant Hypertension (Arteriolar
Nephrosclerosis)
- Acute Mountain Sickness
- Toxic Shock Syndrome
- Colorado Tick Fever
- Caffeine Overdose
- Shigellosis
- Hepatitis A
- Preeclampsia
- Skull Fractures
- Dengue Fever
- Chronic Kidney Disease
- HELLP Syndrome
- Hyponatremia (Low Blood Sodium)
- Encephalitis
- Leptospirosis (Weil's Disease)
- Subdural Hematoma (Bleeding in the Brain)
- Subarachnoid Hemorrhage
- Acoustic Neuroma
- Meningitis
- Brain Abscess
- Brain Aneurysm
- Adult Brain Tumor
- Addisonian Crisis (Acute Adrenal Crisis)
- Medullary Cystic Disease
- Poisoning Due to Black Widow Spider Venom (Black Widow Spider Bites)
- Malaria
- End-Stage Kidney Disease
- Carbon Monoxide Poisoning
- Yellow fever
- SARS (Severe Acute Respiratory Syndrome)
- Ebola Virus and Disease
- Anthrax
- Polio

More and Fast facts on headache

Sequel.
Fast facts on headaches
Here are some key points about headaches.
More detail and supporting information is in the main article.
•Headaches can be stand alone
illnesses or the symptom of another
condition.
•Depending on the specific type of
headache, they can last for any time
between a few hours and several weeks.
•Primary headaches are caused by
problems with or overactivity from pain-
sensitive structures in the head.
•The most common form of primary
headache is the tension-type headache.
•A wide variety of conditions can cause secondary headaches, ranging from
hangovers to brain tumors.
•The most common form of secondary headache is the rebound headache (medication-overuse headache).
•Health care providers will usually
diagnose a headache from a history and description of its symptoms.
•The most common suggested
treatment for headaches is rest and pain relief medication.
•Overuse of pain medication can lead to the development of rebound headaches.
•It is estimated that 50% of people
experiencing headaches self-treat rather than see a health care provider.
Causes and symptoms coming...

Facts about Headache you and I don't know about

These are facts you and I don't know about. See below
Some I don't know, but thanks to research and now THOB is helping you out
1. The head is one of the most common sites of pain in the body.
2. The most common types of headache can be classified as
1) primary
2) secondary,
3) cranial neuralgias, facial pain, and
other headaches.
3. The most common types of primary headaches are
1) tension
2) migraine
3) cluster.
Tension headaches are the most common type of primary headache and usually are treated with over-the-counter (OTC) medications for pain.
Secondary headaches are a symptom of an injury or an underlying illness.
4. Another word for headache is Cephalalgia
5. Headaches doesn't mean pain in the head only, it's also a pain around the head and neck.

Patients should seek medical care for new onset headaches, fever , stiff neck , change in behavior, vomiting,weakness, or change in sensation.

What Headache truly means. - for reference purpose

I decided to post the proper and authentic definition of headache mainly for reference purpose.
Sit calm and read.
What is a headache?
Headache is defined as a pain arising from the head or upper neck of the body. The pain originates from the tissues and structures that surround the brain because the brain itself has
no nerves that give rise to the sensation of pain (pain fibers). The periosteum that surrounds bones; muscles that encase the skull, sinuses, eyes, and ears; and meninges that cover the surface of the brain and spinal cord, arteries, veins, and nerves, all can become inflamed or irritated to cause the pain
of a headache. This pain may be a dull ache, sharp, throbbing, constant, mild, or intense.
Now you know.