Brief Answer:
Can be due to cervical spondylosis.

Detailed Answer:
Hello,
Thanks for posting your query.
The headache related to change in position of head is likely to be related to stiff neck and spondylottic changes in the cervical spine.
It happens primarily due to degenerative changes secondary to age in the cervical spine. Past neck injury may also contribute to the degeneration.

X-ray of neck in lateral view or MRI will help in the diagnosis.

Treatment includes
1. Use of cervical collar helps in immobilisation and brings relief.
2. Medical drugs like pain killers - acetaminophen/ibuprofen and muscle relaxants might be helpful.
3. Methylcobalamin supplements are also recommended for nerve compression symptoms.
4. Cervical isometric exercises are beneficial to maintain the strength of the neck muscles. Neck and upper back stretching exercises, as well as light aerobic activities, also are recommended under the guidance of a physical therapist.
5. Hot fomentation helps in relieving acute symptoms.
6. You can avoid using a pillow.

As you try these measures, I also encourage you to consult an orthopedician for both evaluation and to avail stronger prescription medications (if over the counter medications are not helpful).
I hope this answers your query.
In case you have additional questions or doubts, you can forward them to me, and I shall be glad to help you out.
Wishing you good health.
Regards.
Dr. Praveen Tayal.
For future query, you can directly approach me through my profile URL http://bit.ly/Dr-Praveen-Tayal

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Brief Answer:
Stroke not likely.

Detailed Answer:
Hello.
Thanks for writing again.
If there is no other cardiac abnormality or hypertension or diabetes then chances of stroke are remote just due to this headache.
Hope my answer is helpful.
Do accept my answer in case there are no further queries.
Regards.

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