DEAR DR. ROACH: I read that a new drug, Xofluza, has been approved to treat flu. Is there something about it (if known) that might make it more useful than Tamiflu? — D.C.

ANSWER: Baloxavir (Xofluza) has just been approved by the Food and Drug Administration. There are several potential advantages to baloxavir compared with oseltamivir (Tamiflu). The first is that a single dose is effective, as opposed to the normally twice a day for five days dosing of oseltamivir. The second benefit is that the onset of action is faster, with a decrease in the amount of infectious virus by 99.99 percent within a day. Baloxavir works by blocking synthesis of the flu virus inside the cell. Since it is a different mechanism of action from oseltamivir, in theory, the two drugs could be used together, perhaps in people with critical illness. That has not yet been tested.

Baloxavir is modestly effective. People got better on the drug in just over two days, compared with over three days in people who got placebo. There is no proof of reduction in mortality, but the studies looked at otherwise healthy people, whose risk for death from influenza is low.

One concern about baloxavir is that the influenza virus developed resistance to the drug in up to 10 percent of recipients after a single dose. That raises concern that the drug may lose effectiveness in the population if it is used widely. But that theoretical concern remains to be proven.

Vaccination remains the best way of preventing flu illness, but early treatment (as fast as possible, preferably within 24 hours) with an antiviral medication can make symptoms improve a bit faster.

DEAR DR. ROACH: My 84-year-old husband’s chart has listed him as prediabetic for several years. Two years ago, his A1C was 7. He was then listed as diabetic, and prescribed metformin. Subsequently our HMO has given us free classes on how to deal with the problem. I was a leader for a weight loss group for many years, and he quit eating cream cookies, started walking again, and in three months his A1C was down to a 6 and now is 5.8. His doctor has taken him off the metformin.

The computer thinks he is diabetic, so all his meds are screened so that they don’t affect his diabetes. For two years, he has taken his reading every morning and is beginning to grumble as he feels he is now on the records as a diabetic but isn’t.

We both wonder how many of these folks who are used in national studies are like him. We wonder if you are a diabetic for life once you are in the computer. Can it be changed? — P.V.R.

ANSWER: Your husband (and you) should be immensely proud of getting his A1C down to where he no longer requires medication. Even though his A1C is now in the range called “prediabetes” or “impaired glucose tolerance,” diabetes is considered a permanent diagnosis: Once you have it, it stays. This makes sense. If your husband were to stop his walking, go back to the cream cookies and reverse any other changes he had made, he would be very likely to see his A1C go back up. So, he is considered to have diabetes controlled by diet and exercise.

Having the information in the computer is not all bad. It can identify potentially problematic medications as well as recommend appropriate screening tests for people with diabetes, including eye and foot exams, which probably are still a good idea for him, despite his good control.

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Dr. Roach regrets that he is unable to answer individual letters, but will incorporate them in the column whenever possible. Readers may email questions to ToYourGoodHealth@med.cornell.edu or send mail to 628 Virginia Dr., Orlando, FL 32803.

Dr. Roach