Elderly hypertensive woman always has high bp only in the mornings and it goes down to near normal in about 2hrs even without drugs. what causes it?

Fluid/salt: If one has salty food the day prior, fluid retention may occur; also, in bed, the fluid in ones legs tends to be absorbed, resulting in increased blood volume and pressure by morning. Blood pressure medications are often given at bedtime to help reduce am bp. Am is also the most stressful time for many. This merits a careful medical evaluation. Restrict salt.

Possibilities: Morning high blood pressure may also be a symptom of sleep apnea or other sleep disorders. In addition cortisol levels are at their highest early in the morning. Some BP meds taken in the morning may wear off by the next morning. Salt, caffeine and alcohol intake can also affect BP differently at different times of day.

Very interesting: To help us wake up with energy for the day, our bodies put out hormones that can go too far & increase bp. Healthy folk enjoy this. Weakened cardiovascular folk don't and it can kill them. Many heart attacks happen upon waking for this reason. Ask the doctor to find a BP med that has a longer half-life (micardis (telmisartan) hct is one).