DEAR DR. ROACH: I am wondering if there is any link between low iron and depression/anxiety. I am a 37-year-old woman, and I started taking Lexapro a few years ago. I upped my dose last year because I wasn’t feeling great, and my doctor and I decided that it was a good step to take.

During the years that I have been taking Lexapro, I have also been a regular blood donor. I am CMV-negative, so I have blood suitable for newborns. The Red Cross says I am a “hero for babies,” and I enjoy doing something good.

I haven’t donated in about five months, and I am feeling significantly better regarding my depression. I know that donating blood affects iron levels, but does it also affect the concentration of Lexapro in my body? If not, can low iron be contributing to my depression? I would love to know the answer so that I can possibly continue to donate, perhaps less frequently. — J.M.

ANSWER: First, thank you for donating so regularly. CMV is a virus most people have been exposed to, and like most herpes viruses, it stays in the body forever. Newborns and premature babies, as well as organ transplant recipients, need CMV-negative blood, and there aren’t many CMV-negative people who can donate.

Depression and anxiety are both tightly linked to the neurotransmitter serotonin. Lexapro doesn’t increase serotonin, but it does make the transmission of serotonin from one nerve cell to another more effective by reducing the reuptake of serotonin at the nerve junction. Low iron levels have been shown to reduce serotonin levels, so this may be part of the reason why your depressive symptoms have been worse.

However, there are many other reasons, both inside and outside of your body, that can make depressive symptoms worse. Still, if you do have low iron levels, you can replace iron faster and keep it normal, despite blood donation and menstruation, with an iron supplement. (It would be best to check with your doctor on this.) If your depression gets better, then this would be pretty good evidence that low iron does affect your mood. (Note: You can have low iron and not have anemia at all.)

Find the right donation frequency so you can still help without putting your mental health in danger.

Infection may cause trouble urinating while standing

DEAR DR. ROACH: I am an 86-year-old male in good health. Several years ago, I had about 1/3 of my prostate removed because I couldn’t pee. After the surgery, all was well with a steady stream until about two weeks ago. During one of my many trips to the bathroom, I noticed that I had a hard time when starting to urinate, and the stream was stop-and-go. This continues to this day, but it isn’t a problem during the day.

Any thoughts on my sudden change in urinating? — D.S.

ANSWER: A sudden change in urination should prompt an evaluation for a urine infection. These are quite common with men in their 80s, especially those with prostate problems, even if they have undergone surgical treatment. Your first stop should be your regular doctor for a urine test, and if this doesn’t reveal the problem, it is time to visit your urologist.

Some medicines can dramatically worsen the ability to urinate in men, especially decongestants and antihistamines. Some people use these at night, which might explain why you only experience problems at that time.