DEAR DR. DONOHUE: I have lived an athletic lifestyle for my entire 48 years. I am hesitant to take blood pressure meds that my doctor has prescribed because of the extreme variation in readings taken by him, his nurses and my home unit.

My machine says my blood pressure is 180/105, while the doctor gets 146/100 and the nurse says it is 126/82. My home readings match automated readings at health fairs where the machines are run by professionals. I have taken several models with me for comparison during office visits.

I don’t want to start drugs based on bogus readings or outdated standards for what constitutes high blood pressure. – Anon.

ANSWER: The standards for blood pressure are these: Normal is anything below 120/80; high, anything equal to or above 140/90. Numbers in between those two units are called prehypertension.

If, in the doctor’s office, your machine gives the same readings as your doctor’s, then your home high reading should be accepted as your blood pressure. The office reading obtained by your doctor also constitutes high blood pressure. In both cases, your pressure requires treatment. I can’t explain the lower reading the nurse got.

If you don’t believe the office reading, ask your doctor to call two of his friends and have your pressure taken at their offices. Take your home machine along with you to check its accuracy.

Or you can have your blood pressure checked over a full 24 hours by wearing a device that records pressure throughout the day and night. A high home reading with a lower office reading is the opposite of what usually happens. The anxiety of being in the doctor’s office often raises blood pressure.

You have to take the reading according to the rules. You should be seated and relaxed for a full five minutes before taking your pressure. The arm in which pressure is recorded should be supported and resting at heart level. If your cuff is too small, you get a falsely high reading. Don’t drink or eat anything with caffeine or smoke for at least 30 minutes before taking your pressure.

DEAR DR. DONOHUE: In the past two years, I have had episodes of loss of sensation on my right side, including my lip, lower right arm and lower right leg. In April 2005 I had a brain MRI (report enclosed). A neurologist said I had a migraine equivalent. In 2007, I had vertigo and another MRI. A different neurologist did not have an answer for my loss of sensation and suggested an EMG, which I declined. I am terrified of having a stroke. At times I still have symptoms and sometimes a headache. What is microvascular disease? Should I get a third opinion? – T.L.

ANSWER: Your MRIs show no evidence of stroke. The radiologist noted “very minimal microvascular disease.” “Microvascular” indicates that minute arteries might be clogged. The “very minimal” says the process is hardly worth mentioning and is something that could be found in anyone your age (55).

Why not have the EMG – electromyogram, a test that can show changes in nerve function, which could produce episodic numbness? You might get the answer to your question.

A third consultation isn’t outlandish if it will give you peace of mind. We all fear strokes. The stroke booklet deals with the common and often catastrophic ailment. Readers can obtain a copy by writing: Dr. Donohue – No. 902, Box 536475, Orlando, FL 32853-6475. Enclose a check or money order (no cash) for $4.75 U.S./$6 Can. with the recipient’s printed name and address. Please allow four weeks for delivery.

Dr. Donohue regrets that he is unable to answer individual letters, but he will incorporate them in his column whenever possible. Readers may write him or request an order form of available health newsletters at P.O. Box 536475, Orlando, FL 32853-6475. Readers may also order health newsletters from www.rbmamall.com