It is safe to have the pertussis vaccine while pregnant?

DEAR DOCTOR K: I am pregnant. My doctor wants me to have a pertussis vaccine. Why? And is this safe?

DEAR READER: Pertussis, also known as whooping cough, is a highly contagious bacterial infection that causes violent coughing. The coughing makes it hard to breathe and produces a deep "whooping" sound. Pertussis bacteria spread through droplets that move through the air when an infected person sneezes, coughs or talks. Pertussis can occur at any age, but serious illness is most common in infants and young children.

Is mourning a pet a normal reaction?

DEAR DOCTOR K: My beloved dog passed away a few months ago after years of loving companionship. My friends think I should be over his death by now. Are they right?

DEAR READER: There's a reason dogs are called man's (and woman's) best friend: They offer unparalleled companionship and unconditional love. Especially unconditional love. That love is encapsulated in the wonderful prayer: "Lord, help me to become the person that my dog thinks I am." For most dog owners, a dog is a cherished member of the family.

I found out I have a kidney infection from a UTI, why didn’t I have any other, earlier symptoms?

DEAR DOCTOR K: I am a woman in my 80s. I went to my doctor because I suddenly developed back pain. It turned out to be a urinary tract infection that had spread to my kidneys. Why didn't I have any other, earlier symptoms?

DEAR READER: If you had urinary tract infections (UTIs) when you were younger, you probably remember the burning, pain and intense urge to urinate frequently. But these symptoms don't always appear in older adults. UTIs commonly occur when bacteria from the rectum (such as E. coli) infect the skin around the opening of the urethra (the tube leading to the bladder).

Has colonoscopy prep changed in the last decade?

DEAR DOCTOR K: It's been 10 years since my last colonoscopy. I'm dreading my next one, especially drinking a gallon of liquid laxative. Has colonoscopy prep gotten more tolerable in the last decade?

DEAR READER: Yes, but that still doesn't make it fun. And you can't avoid it: You want the doctor to be able to clearly see every inch of your colon. For that, you need a good cleanout. As you probably know, getting a periodic colonoscopy really is important. Simply put, it reduces your risk of getting and dying from colon cancer. These cancers, and growths that can turn into cancer (polyps), not only can be spotted by colonoscopy:

I’m obese. Should I be on a weight-loss drug to lower my heart disease risk?

DEAR DOCTOR K: I take medications for high blood pressure and high cholesterol. I am also obese, which is another risk factor for heart disease. Should I be on a weight-loss drug?

DEAR READER: You're right that being obese can put a heavy burden on your heart. It boosts your heart attack risk by about 60 percent. Diet and exercise are always the first steps toward controlling excess weight and other heart disease risk factors. When lifestyle changes aren't enough, doctors often prescribe medications, like statins for high cholesterol. But the medical options for weight loss are more limited.

What is hydrocephalus and how is it treated?

DEAR DOCTOR K: My father had been showing signs of dementia for a few months. We thought it was Alzheimer's disease, but it turned out to be hydrocephalus. What is this, and how is it treated? Does the condition cause permanent brain damage?

DEAR READER: Hydrocephalus is a condition in which extra cerebrospinal fluid collects inside the brain. (Another name for it is "water on the brain.") Cerebrospinal fluid acts as a cushion for the brain and spinal cord. It also supplies nutrients and removes waste products. (I've put an illustration of a brain affected by hydrodcephalus, below.)

What can I do about my esophagitis caused by acid reflux?

DEAR DOCTOR K: I have esophagitis. Could this have been caused by my acid reflux? What can I do about it?

DEAR READER: Yes, it could, and there are treatments. First, some explanation. The esophagus is the muscular tube that carries food from the mouth, through the chest and into the stomach. Normally you don't feel the presence of the esophagus, except when you are swallowing. Sometimes the lining of your esophagus becomes inflamed. That's called esophagitis. By far the most common cause of esophagitis is acid reflux, or gastroesophageal reflux disease (GERD).

My doctor advised active surveillance for my prostate cancer. What does this mean?

DEAR DOCTOR K: After an abnormal PSA test and biopsy, I have been diagnosed with early-stage, non-aggressive prostate cancer. My doctor advised active surveillance. What does this mean?

DEAR READER: Prostate cancer is the uncontrolled growth of abnormal cells in the prostate. This walnut-sized gland sits below the bladder, in front of the rectum, near the base of the penis. Prostate cancer is common, but it is not always dangerous. People are often surprised to hear "cancer" and "not dangerous" in the same sentence.

Can ibuprofen reduce my heart attack risk as well as my pain?

DEAR DOCTOR K: I take ibuprofen every morning for my arthritis. My doctor wants me to take low-dose aspirin every day to reduce my heart attack risk. Ibuprofen and aspirin are both NSAIDs, right? So will the ibuprofen help my arthritis and my heart? Or should I take both?

DEAR READER: When joints ache, many people turn to nonsteroidal anti-inflammatory drugs (NSAIDs) for pain relief. Aspirin is a type of NSAID. So are ibuprofen (Advil, Motrin) and naproxen (Aleve, Naprosyn). NSAIDs are widely used because they perform double duty. They relieve pain and also reduce inflammation.

Do any supplements effectively lower cholesterol?

DEAR DOCTOR K: My cholesterol is high and my doctor wants me to go on a statin. I'd like to avoid medication. Do any supplements effectively lower cholesterol?

DEAR READER: Statin drugs lower LDL (or "bad") cholesterol and also reduce inflammation. Together, these effects lower your risk of heart attack. Various herbs and supplements have been touted for their ability to improve cholesterol levels. There is one general caveat you should consider. New drugs are tested by the FDA for their safety, effectiveness and purity.