People’s Pharmacy: Nurse complains about faulty BP measurement technique

Q. I am a retired registered nurse, and I find that blood pressures are not taken correctly, whether it is the dentist’s office, when donating blood, in the family practice office, etc. Practitioners at all levels often fail to follow all guidelines; frequently there are several errors in technique.

I often wonder about the point of even measuring blood pressure if it is not done correctly. It is disturbing to think how many people are probably being treated for high blood pressure when it is not even taken correctly in the office of the doctor prescribing the medicine.

A. High blood pressure leads to a lot of misery including heart attacks and strokes. That’s why it is critical to measure blood pressure accurately.

Here are some guidelines: Patients should be encouraged to empty their bladders before a blood pressure measurement (Hypertension, May 2019). They should be allowed at least 5 minutes to sit quietly in a comfortable chair with their back supported and the arm resting at heart level. The blood pressure cuff must be the right size for the arm. If it is too small, the reading could be falsely elevated. A study of home blood pressure devices reveals that most come with an arm cuff that is too small for many people (Hypertension, Sept. 5, 2024).

Taking your blood pressure at home does make sense if you do it properly. You can learn more about measuring and controlling high blood pressure in our “eGuide to Blood Pressure Solutions.” This online resource is available under the Health eGuides tab at www.PeoplesPharmacy.com.

One reader points out why you should measure your own blood pressure: “I have 40 years of experience in the medical arena. I am 80 years old, and I take my blood pressure three times a day. I don’t believe my blood pressure has ever been taken correctly given all the parameters. My BP is different depending on the time of day.”

Q. Thank you for writing about the side effects of metformin. I have been on it for at least 15 years, and now I am starting to have trouble with numbness and tingling, usually at night. Horrific leg and foot cramps are depriving me of much-needed sleep. Could metformin be causing these problems?

A. Your doctor should be monitoring your vitamin B12 level. Metformin can deplete the body of this crucial nutrient, especially if taken over a long period of time.

Symptoms of vitamin B12 deficiency include balance problems, weakness, confusion, memory problems, numbness and tingling in hands and feet, burning tongue and depression.

Another problem with long-term metformin use is low magnesium (American Journal of Clinical Nutrition, June 2024). This could contribute to the nighttime cramps troubling you.

Q. I have struggled with itchy scalp. I started using Nizoral shampoo a few years ago.

Often, I first wash my hair with Head & Shoulders, then rinse well and shampoo again with Nizoral. This method works well for me to control my itchy scalp. Nizoral is a bit expensive, but it’s a great product for dandruff.

A. You have created an innovative approach to dandruff. Nizoral was once a prescription-only shampoo, but it has been available for years as an over-the-counter product. The active ingredient, ketoconazole, is a powerful anti-fungal compound that helps control the Malassezia yeast that contributes to itchy flakes. Adding another anti-dandruff ingredient, zinc pyrithione from Head & Shoulders, probably creates an especially effective anti-dandruff treatment.

In their column, Joe and Teresa Graedon answer letters from readers. Write to them in care of King Features, 628 Virginia Drive, Orlando, FL 32803, or email them via their website: www.PeoplesPharmacy.com. Their newest book is “Top Screwups Doctors Make and How to Avoid Them.”