The headache phase is typically, but not always, the most debilitating phase of a migraine attack. It is important to note that symptoms are not limited to the head: they may affect other parts of the body as well.

The pain of the headache phase can range from mild to severe. Sometimes people suffering mild pain may not realise that they are indeed suffering from a migraine.

Symptoms and characteristics of the headache phase may include:

- Frequently unilateral (one-sided) head pain - the headache shifts from one side to the other, or becomes bilateral (on both sides)

- Often pulsating or throbbing

- Worsened by physical activity

- Duration of 4-72 hours in adults, 1-72 hours in children

- Pain may occur around the eyes, in the sinus area, teeth and jaw

- Confusion

- Dehydration

- Dizziness or vertigo

- Depression, anxiety, panic

- Nausea and/or vomiting

- Neck pain

- Diarrhoea or constipation

- Fluid retention

- Hot flashes and/or chills

- Nasal congestion and/or runny nose

- Heightened sensitivity to odours, sounds or light

The headache phase is often followed by the postdromal "hangover" phase.