Blood pressure has a daily (diurnal) pattern like many body functions, . During the night, blood pressure decreases as we sleep, and continues to remain at lower values when the individual in question wakes up. However, as soon as he/she moves his/her body for the first time after waking up, a spike in blood pressure may be seen, which continues to gradually raise over the course of the day, ultimately peaking out at some point in time around high noon. Then, as the afternoon passes by and evening nears, the blood pressure of the body starts to fall once again.

Factors that may cause an abnormal daily pattern, such as high blood pressure in the morning, include:

* Certain medications, such as corticosteroids
* Night-shift work
* Caffeine use
* Tobacco use
* Too much stress can also be main factor
* Poorly controlled high blood pressure
* Sleep apnea
* Tumors of the adrenal gland can also raise blood pressure in morning
* If we have Kidney disease

If you are taking blood pressure medicines then this daily pattern can alter this daily pattern as some medications may not last a full 24 hours. Other medications taken at bedtime are formulated in such a manner that they start working a few hours before you wake up to control the morning surge in blood pressure.

Your doctor can evaluate the significance of an abnormal daily blood pressure pattern. He or she may recommend a 24-hour blood pressure monitoring test. The device used for this test measures your blood pressure at regular intervals over a 24-hour period and provides a more accurate picture of blood pressure changes over a typical day and night.