Q: Whenever my 45-year-old husband has gone to the doctor over the past eight months, he has ben told that his blood pressure is high; but his blood pressure is normal when measured with the device in our local supermarket. Do you agree with his doctor who now has recommended that he take a medication to lower his blood pressure?
A: Blood pressure readings are considered too high when they exceed 140 systolic and/or 90 diastolic, and certainly no medication should be considered unless pressures exceed these values on a regular basis.
An elevation in blood pressure that occurs only when measured by a doctor, referred to as "white coat hypertension" -- undoubtedly related to anxiety -- is quite common.
One way to find out if your husband has real or white coat hypertension is to have him measure his blood pressure on a regular basis when he is home or have it checked by a nurse or other medically trained personnel where he works.
For home checking, he needs to obtain an accurate blood presure measuring device and some instructions on how to use it. The readings from the supermarket alone are not adequate because of uncertainties about their accuracy.
If home monitoring shows consistently normal blood pressure readings, medications to lower the blood pressure might still be considered if his doctor has identified some evidence of organ damage that is most likely caused by hypertension.
If the blood pressure is consistently over 160 systolic and/or 90 to 100 diastolic, most physicians in this country agree that medications should be started to diminish the danger of a stroke, kidney disease and a heart attack.
Dr. Margolis is professor of medicine and biological chemistry at the Johns Hopkins School of Medicine.