Some people may need a second pneumonia vaccine

Q: I'm confused about how often a person should get the pneumonia shot. I've heard different answers - once or twice in a lifetime, and every five years. Which is correct?

A: There continues to be debate over when to get the pneumonia shot (Pneumovax), and some experts aren't sure whether a second shot is beneficial.

I'd suggest staying with current CDC guidelines for adults, which call for a second shot in certain cases.

Bacterial pneumonia claims more lives than the flu each year. The shot helps protect against pneumonia caused by strep bacteria (Streptococcus pneumoniae), the most common type found in the community setting.

The lung infection may visit after a cold or flu has paved the way for pneumonia bacteria to invade the upper respiratory tract.

Following CDC guidelines, you'd get an initial pneumonia shot if you:

-- Are 65 years or older.

-- Have certain medical conditions (e.g., heart disease, lung disease, diabetes).

-- Have low resistance to infection due to disease or drug treatment that curbs the immune response.

-- Are an Alaskan Native or are from certain Native American populations.

You'd get a second pneumonia shot if you:

-- Are 65 years or older and received your initial shot before turning 65.

-- Have low resistance to infection due to disease or drug treatment.

The second pneumonia shot should be given at least 5 years after the initial shot.

Those older than 65 who got the initial shot at age 63, for example, are eligible for a second shot at age 68 or later. If you're older than 65 when you get your initial shot, a second shot is not routinely recommended.

Getting more than two shots is not recommended, no matter how long ago you received the second shot.

For convenience, the pneumonia shot can be given at the same time as the flu shot. Just roll up your other sleeve.

It's worth noting that stomach acid-suppressing drugs, widely used for ulcers and esophageal reflux, have been associated with boosting the risk of pneumonia.

These drugs include proton pump inhibitors (omeprazole, Aciphex, Nexium, Prevacid, Protonix, and Zegerid) and H2-blockers (cimetidine, famotidine, nizatidine, and ranitidine). Some are available as OTC products.

Stomach acid normally neutralizes ingested bacteria and viruses. When acid is diminished (as with these drugs), disease-causing microorganisms can more readily proliferate in the upper GI tract and work their way into the lungs via the airway.

The more potent proton pump inhibitors appear to increase the risk more than H2-blockers. When needed, these agents should be prescribed at the lowest effective dose.

The biggest concern is for people most susceptible to pneumonia, including the elderly and those with impaired immunity or lung disease.

In many cases, the benefits of acid-reducing agents may outweigh the risk. Don't stop prescribed therapy without checking with your doctor.

A alternative for some might be the drug sucralfate (Carafate), which doesn't suppress stomach acid. And patients should receive the pneumonia shot when appropriate.

Richard Harkness is a consultant pharmacist, natural medicines specialist, and author of eight published books. Write him at 1224 King Henry Drive, Ocean Springs, MS 39564; or rharkn@aol.com . Selected questions will be used in the column.