Q. A reader recently suggested eating sunflower seeds to stay awake while driving. I, too, have looked for an antidote to feeling drowsy while driving. I thought eating something small would help. I didn't want to take in any more calories than I had to.

It occurred to me that maybe the act of chewing would work just as well as actually eating something, so I tried sugar-free gum. It worked like a charm! Whatever the reason, gum almost always keeps that drowsy feeling away, so I keep several packs of gum in the car at all times.

A. Thank you for offering an alternative to sunflower seeds. According to a review of the medical literature, "Many of the studies indicated that chewing exerts a positive effect on attention, and especially on sustained attention, in addition to improved mood and stress relief" (Biomed Research International, online, May 17, 2015).

We remind those who are not accustomed to chewing gum with sorbitol or maltitol that such sugar substitutes can cause diarrhea if you consume too much of them.

Q. I read on your website about the new flu drug called Xofluza. I had to laugh at the side effects of diarrhea, bronchitis, nausea and sinusitis. Wait, isn't that just like the flu?

A. Baloxavir (Xofluza) is the first new oral flu drug to be approved in nearly 20 years. Like oseltamivir (Tamiflu), it shortens the duration of flu symptoms by about one day. It must be started within the first 48 hours of symptoms to be effective.

The side effects of Xofluza are no more common than with placebo. In the clinical trials, diarrhea occurred in 5 percent of people on placebo and 3 percent of those on Xofluza. Bronchitis was a problem for 2 percent of those taking the drug and 4 percent of subjects on placebo. Other symptoms were reported by 1 percent of those taking Xofluza.

One advantage of this new prescription flu medicine is that you take only one dose. Unfortunately, the drug is pricey ($150 to $160).

Q. My doctor determined by blood tests that my thyroid levels remain stable only when I take the original drug, Synthroid. Whenever I go to a new pharmacy, they always say that the only thyroid drug they can get is generic levothyroxine. They always say Synthroid can be special ordered but it will take time to get it.

It is always a lot more expensive than the generic pill and not covered by my insurance. Why do they make it so hard to get the drug I need?

A. Synthroid is a long-standing brand-name version of levothyroxine. You are right that it is more expensive than the generic medication. Synthroid runs between $45 and $67 for 30 pills. The generic version costs between $12 and $16 for the same 30 tablets. That's why many insurance companies only want to pay for generic levothyroxine.

We discovered that brand-name Synthroid is substantially less expensive from Canada. A three-month supply costs between $25 and $60, less than a 30-day bottle from the U.S.

Write Joe and Teresa Graedon at www.PeoplesPharmacy.com.