Sudden Severe Headache
You must seek medical advice if you have just experienced a sudden severe headache for the first time.
The most serious type of sudden headache is called a Thunderclap Headache.
In a Thunderclap Headache, pain goes from zero to worst ever headache in about 1-2 seconds. This type of pain can involve the entire head or both sides at the back of the head.
The pain always affects both sides. For some reason the front of the head is not often affected on its own.
Thunderclap head pain lasts many minutes or hours, not seconds.
However, in about 10% of thunderclap headache cases a brain haemorrhage called subarachnoid haemorrhage is the cause.
In many cases, a definite cause for sudden severe headache is not identified.
However, this is now an area of intense research activity.
There are now many conditions thought to be causes of Thunderclap Headache. Recently the focus has been on a condition called Reversible Cerebral Vasoconstriction Syndrome (RCVS).
In RCVS it is thought that spasm of arteries in the brain can lead to sudden head pain due to irritation of nerve endings in the linings of the brain's arteries.
Please note that sudden pains lasting seconds or fraction of a second are not serious.
Very brief severe head pains are called neuralgiform headaches or idiopathic stabbing headaches or ice pick headache.
What Causes Sudden Headache?
The most important point in the history of sudden severe headache is to identify exactly what you were doing at the time the headache started.
Sometimes sudden headache is provoked by Sex or Exercise.
Coughing can trigger sudden severe pain, especially in the back of the head.
Even sleep can bring on a strange headache called Hypnic Headache.
This can cause repeated bouts of sudden intense pain which waken from sleep nearly every night, yet can be easily treated in many cases with lithium carbonate.
Lithium carbonate treatment requires careful medical supervision due to risk of long term side-effects.
Know Exactly How Long from Start to Maximum Pain
Once you know if there were any activites that triggered the pain, the next question is to try and estimate accurately how long it took for the head pain to reach its worst.
I say this every day in my own practice - "...from the start of your headache until it reached its worst, how long did it take?"
If a history is taken clearly like that, then you can avoid being labelled incorrectly with thunderclap headache, when it might actually be a bad migraine which was building slowly for a few hours and then over a few minutes intensified.
On the other hand if someone has developed a headache of several hours or days duration, it is just as important to get a description of the exact moment of onset of the original head pain as it is to describe the pain that is now present.
If the onset of headache is not appreciated you can end up doing unnecesary tests, or you could have had a diagnosis of a serious headache delayed.
The bottom line is that sudden severe headches should always be discussed with a doctor, and a single first ever headache episode of sudden severe head pain should be treated urgently.
Read about other Headache Types
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