DEAR DR. ROACH >> Is there anything I can do to relieve the pain and suffering from oral lichen planus?

— Anon.

Dear anon. >> Nobody knows what causes lichen planus, an uncommon (less than 1% of people) skin condition that may also affect the mouth or vagina. It most often occurs during the ages of 30 to 60. It is more common in people with a history of hepatitis C.

Medical students are taught the four “P’s” of lichen planus: pruritis (itchy, often intensely itchy), purple, polygonal, plaques (raised lesions). The plaques often have fine white lines, especially in the condition you are asking about, oral lichen planus. Oral lichen planus often causes pain, especially when eating.

The most effective treatment for oral lichen planus is a potent topical corticosteroid, such as clobetasol, usually placed on the affected areas with a cotton swab. There are some techniques for keeping the medicine on the affected areas that your dermatologist can tell you about.

People who do not respond to topical steroids (it can take a couple of months to get maximum effect) are usually treated with a more powerful medicine, such as tacrolimus. In my experience, lichen planus is usually relieved by treatment — though, perhaps not 100%. In most people, lichen planus mysteriously disappears within a few years of it coming on.

DEAR DR. ROACH >> Because I had Clostridioides difficile (C. diff), I lost 14 pounds. Now that I am cured of the C. diff — thanks to a fecal transplant after every other treatment failed — I’m wondering if I’ll ever gain back the weight or if it is gone forever? I didn’t have 14 pounds to lose!

— E.G.

Dear e.g. >> In my experience, weight loss that happens during a significant illness usually comes back in weeks. I don’t know how long it has been since you had C. diff, but if it hasn’t been so long, I’d expect you to regain the weight. The body has a “set point” of weight that it likes to stay at.

However, the fecal transplant may affect the set point. In lab animals, and in some preliminary studies in humans, a person’s weight set point can be partially affected by their intestinal bacteria.

The potential of getting someone to lose weight by transplanting the intestinal bacteria is limited, though, as most of the data show that the weight reductions are not maintained. (One review of many studies showed the weight loss was gone by 18 weeks.)

A registered dietician or nutritionist can give you personalized advice on a healthy diet to help regain weight.

DEAR DR. ROACH >> I am a 76-year-old female. In your opinion, should I continue to have annual exams by my gynecologist?

— P.A.

Dear p.a. >> The evidence is strong that Pap smears are of little value in (most) women over 65, but I still believe a woman should continue to see a gynecologist (or whomever she has been seeing for routine gynecologic care). There are many concerns a woman has as she gets older, and common conditions benefit from a relationship with a provider expert in women’s care.

Contact Dr. Roach at ToYourGoodHealth@med.cornell.edu.