Too long between Shingrix doses

DEAR DR. ROACH: Three years ago, I turned 60 and received my first dose of Shingrix. I had a highly unpleasant reaction, with fever and flulike symptoms. I did not return for the second dose until last week, so although I have had two doses, they are three years apart. Do I need to get another dose in a short window of my most recent vaccination or will I be considered protected since I have had two doses, just significantly spaced apart? By the way, no reaction this round other than a sore arm!

ANSWER: The new two-dose shingles subunit vaccine (Shingrix) is a highly effective treatment to prevent shingles and its complications. It is recommended you get the second dose two to six months after the first dose. According to the Centers for Disease Control and Prevention:

“The vaccine series need not be restarted if more than six months have elapsed since the first dose; however, the efficacy of alternative dosing regimens has not been evaluated, data regarding the safety of alternative regimens are limited, and individuals might remain at risk for herpes zoster during a longer than recommended interval between doses 1 and 2.”

Despite that somewhat reassuring statement, three years seems to be pushing it to me, and I would really consider getting a third dose two to six months after the dose you just took. You may (or may not) get a reaction, but you would be surer about having protection against shingles.

DEAR DR. ROACH: I had my thyroid removed in 2004 due to papillary carcinoma. I see an ear, nose and throat doctor once a year, at which time I have an ultrasound of my neck area.

My primary care physician orders blood tests every three months to primarily determine if my levothyroxine dosage is correct.

Please advise which thyroid-related blood tests that you would recommend to monitor my level of medication. My ENT told me that an incorrect dosage may result in heart issues.

ANSWER: Measuring the thyroid hormone itself, levothyroxine, and thyroid stimulating hormone, made in the pituitary, are adequate to monitor the thyroid level in most people.

There is a fairly broad range of these hormones, but when both are in the normal range, that’s usually a good place to be. If the thyroxine level is low, the body responds by increasing the TSH level. If thyroxine is high, the TSH level goes way down. It’s when thyroxine is high that the heart can be damaged, particularly by the development of atrial fibrillation.

In most people with a history of thyroid cancer, experts recommend a thyroxine level just on the high side of normal. That means the TSH level will be low-normal, which is desired because some cancer cells can be stimulated by high levels of TSH.

In patients with a higher risk of cancer recurrence, the TSH level may need to be suppressed even below the lower limit of normal.

Frequent checks of the thyroid are appropriate to be sure your thyroid levels are not so high that you are at increased risk for developing the heart problems of excess thyroid levels. Other health issues also may occur, such as bone loss. It’s a delicate balancing act between reducing cancer recurrence risk but not damaging the rest of the body.

DEAR DR. ROACH: So much is written about the dangers of high blood pressure — “the silent killer” — but very little about low blood pressure. Low blood pressure is not silent. It can make life miserable. Is there a way to safely raise one's BP? ANSWER: Physicians may not seem to care as much about low blood pressure readings than high, partially because healthy people with low blood pressure have a lower risk of heart disease.

However, there are many medical conditions where a low blood pressure is a cause for concern — sepsis in particular is exceedingly dangerous when accompanied by low blood pressure. Heart failure with low blood pressure is concerning. I’m going to assume you mean low blood pressure that has been persistent and not as a result of other medical illness.

High blood pressure often does not have warning signs (some people will have headache or other symptoms), but low blood pressure can cause lightheadedness or fatigue.

Although some people have symptomatic low blood pressure at any time, for most people, symptoms are worst when changing position, particularly when going from laying down to sitting or standing, but also from sitting to standing. This situation is called orthostatic hypotension (which literally means “upright posture low blood pressure”).

Others may develop symptoms after prolonged standing, a situation sometimes called chronic orthostatic intolerance. Orthostatic hypotension is common (20% or more) in healthy older adults. It may also be due to medication. There are common and uncommon neurological syndromes that can cause orthostatic hypotension.

Many people, even after extensive evaluation, will not have an identifiable cause of low blood pressure. In this case, first-line treatment is changing behaviour; specifically, getting up slowly, along with taking in extra salt and water. Those who don’t respond adequately may benefit from medication treatment.

There are additional treatments, but treatment must be individualized.

Cardiologists and hypertension specialists often have expertise in conditions of too-low blood pressure.

Readers may email questions to ToYourGoodHealth@med.cornell.edu or write to 628 Virginia Dr., Orlando, Fla., U.S.A., 32803.