Q: After seeing many top doctors who told her to eat a bland diet of bagels and pasta for her irritable bowel syndrome, my sister consulted Dr. Peter Green at Columbia Medical Center. There, she was given appropriate tests and diagnosed with celiac disease. That may have saved her life.

It used to be hard to find gluten-free foods. Now they’re everywhere.

A: Celiac disease is finally getting the attention it deserves. This is an autoimmune condition in which the intestinal lining is damaged by the presence of gluten, found in wheat, barley and rye.

When susceptible people are exposed to foods like those recommended to your sister, they may suffer intestinal symptoms, migraines, skin rash, osteoporosis, joint pain or brain fog, among other problems. This condition also may increase the risk for lymphoma (Annals of Internal Medicine, Aug. 6, 2013). The treatment for celiac disease is to follow a strict gluten-free diet (no bagels or pasta).

The Food and Drug Administration has just issued a definition for gluten-free foods that restricts gluten to no more than 20 parts per million. The new standard should make it easier to find safe, gluten-free foods.

Q: I would like to know what has happened with the FDA’s investigation into generic Wellbutrin (bupropion). Has anyone heard about the results of the studies that were supposed to be completed by March 2013?

There is not a word on the FDA website. Even if the results were late, it’s now been several months.

I was on the brand for years, since the generic didn’t work for me. Now my insurance company will not pay for the brand name, so I’m forced to switch back to the generic. I’m worried about getting depressed again.

A: Last fall, the FDA admitted that one generic form of bupropion (Budeprion XL 300) was not bioequivalent to the brand name Wellbutrin XL 300. The formulation was removed from the market.

At that time, the FDA asked other generic manufacturers to complete further tests by March 31, 2013. We have repeatedly asked the FDA for the results of these tests, but we have not yet seen a report or any data. Your doctor may be able to appeal to the insurance company on your behalf.

Q: After reading about hydrogen peroxide and Listerine, I wanted to add my method for treating mosquito bites. This was used on me when I was a child. With a cotton ball, dab Cepacol mouthwash on the bites. This stops the itching immediately.

A: We have heard from other readers that applying amber Listerine or hydrogen peroxide immediately can stop the itch of a mosquito bite. Cepacol mouthwash contains some of the same inactive ingredients as Listerine, in particular the alcohol base, eucalyptus oil and methyl salicylate (oil of wintergreen). Perhaps one of these is responsible for the itch relief.

Joe and Teresa Graedon answer letters from readers. Write to them in care of this newspaper or email them via their Web site: www.PeoplesPharmacy.com. Their newest book is “Top Screwups Doctors Make and How to Avoid Them.”