Brief Answer:
tension headaches most common cause

Detailed Answer:
HI, thanks for using healthcare magic

Headaches can be related to inadequate fluid intake but there are other causes.

Headaches can be primary or secondary to trauma, infection or some other disorder.


The main causes of primary headaches are: (1)migraines

(2)tension headaches

(3)cluster headaches

(4)other primary headaches- eg primary cough headache or due to exertion in some persons

Headaches can also be secondary as mentioned above. These are headaches that can be related to infection, trauma, sinusitis, blood disorder in the head or brain, side effect of medication, drug withdrawal.

If there are no likely secondary causes as mentioned above then you can focus on likely primary cause.

Tension headaches are most common- they are normally pressing or tightening, front or the very back of head or involve both sides of the head, not worsened by physical activity
Not all of these characteristics need to be present, just 2 for diagnosis

Additionally not normally associated with nausea/vomiting, may have stiffness in neck and shoulders, may be affected by light and/or sound

Tension headaches are treated with relaxation techniques, pain medication, ensuring adequate rest and exercise , balanced meal, stretching

Migraines are normally severe, one sided, throbbing headaches can last for days. Associated with nausea/vomiting, worse with activity, worse with light and sound.
There are specific triggers.

These 2 are most common.

Your doctor can determine which is most likely via history and physical examination.
Pain medication can be given to help with pain relief

I hope this helps, feel free to ask any other questions

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