Brief Answer:
Low blood pressure may be a cause

Detailed Answer:

Hi,

Reading at those values you mention the blood pressure values are very low. That could be a possible cause for the headaches. Usually the most common cause is insufficient water intake. So taking plenty of water and caffeine would be two simple initial measures. If blood pressure values remain persistently low then some blood tests should be considered to search for other possible causes such as metabolic or hormonal issues (blood glucose, liver and kidney function, electrolyte panel, blood cortisol and parathormone levels). A heart evaluation possibly including an ultrasound may also be considered.

Of course there is also the possibility that low blood pressure is not the cause. There are individuals who have a persistent low blood pressure all their lives without any symptoms, no intervention is needed in such cases apart from water. So if she has had measurements in the past consistently at those values then other headache causes other than blood pressure must be considered. For that though some more information regarding headache characteristics would be needed, info on headache location, variations during the day, character (throbbing, pressure-like, lancinating etc.), accompanying symptoms (nausea, vomiting, increased sensitivity to light, nasal congestion, neck stiffness etc.).

I remain at your disposal for other questions.

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