Crying is much better than keeping the emotional stressor to be bottled up inside. It is a form or release, to let everything out, that is why it feels good after a good cry, but not always. Sometimes the aftermath is a monster headache. Why do we feel intense headache after a hard cry? Don’t ask me why I cried to come up with this post, but the head felt like it would explode. There’s not much medical info about it but the most plausible reason is that: when crying,

The pulse and heart rate increase, your breathing quickens, you take breaths often in large grasps and hold it in between. Thus the oxygen level in our blood is reduced, therefore, reducing the amount of oxygen going to your brain. With less oxygen, the capillaries and blood vessels become smaller. When you start taking in more oxygen, taking deep breaths/grasps, your body is trying to pump the blood/oxygen through to your brain, but the capillaries are already smaller and more blood flows to your head. Intracranial pressure increases when excessive blood flows to your head and the subsequent stretching of the blood vessels, producing a throbbing to intense headache caused by heightened blood pressure, which takes a little longer to recover than the rest of the body. Lack of oxygen can cause muscle cramps, they say when we cry we use the same muscles when we frown, that number of muscles become much more tense throughout the body, especially in the head/face/neck/chest as you tend to strain during hard crying. These physical reactions plus the reason that made you cry all cause a great deal of tension and stress, and in crying hard, all of these produce a stronger reaction, which can totally lead to a monster headache.

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