DEAR DR. ROACH: I have suffered from chronic low back pain that affects my knees. I have seen at least six physical therapists, and nothing helps. At times, I have been prescribed 4 mg of methylprednisolone for six days. It helps calm inflammation down and helps me move without severe pain. (I still have pain, but it’s not as severe.)

I’m wondering if it would be harmful to take this low dosage indefinitely. When I am not taking it, I cannot move without severe pain. I cannot turn over in bed without pain, and I’m unable to stand or walk short distances without pain. — A.C.

ANSWER: In my opinion, the first thing you need is a diagnosis of what’s causing your knee pain. Although osteoarthritis is a very common cause of back and knee pain, oral steroids like methylprednisolone are not an appropriate treatment for osteoarthritis or occasional flares, especially chronic use.

Oral steroids have terrible long-term side effects that make them far too toxic to use for osteoarthritis. The list of potential damage is too long for the column, but it is common to see elevated blood pressure levels, weight gain, diabetes, and osteoporosis.

The fact that there seems to be so much inflammation would make me concerned about other types of inflammatory arthritides. Rheumatoid arthritis commonly favors the hands but can also affect the back and knees. Lyme disease, gout, pseudogout, psoriatic arthritis, lupus, inflammatory bowel disease and hemochromatosis are all important considerations as well. Some of these do get better with a steroid like methylprednisolone.

If you have not seen an expert, I recommend a rheumatologist who will perform a careful exam, lots of blood tests and some X-rays of your knees and back. Once you have a diagnosis, you can get a more appropriate treatment plan.

DEAR DR. ROACH: I understand that there can be possible health issues from consuming “raw” cow’s milk (i.e., not pasteurized). Are there similar risks from cheese made from “raw” milk? — A.R.L.

ANSWER: Although cheese made from unpasteurized milk has been consumed for centuries, it is still possible, even with the very best care, for cheeses to contain bacteria that is capable of causing serious illness. There are frequent recalls of raw cheese because of infections from listeria, salmonella and E. coli.

People who consume cheese made from raw milk risk developing a severe infection, especially if they are very old or very young or have a problem with their immune systems.

At the current time, there is avian influenza spreading among dairy cows, and infectious avian flu has been found in unpasteurized cow’s milk. Pasteurization makes the milk safe to drink, so while I never recommend raw milk or cheese, it is particularly important to avoid raw milk and cheese made from raw milk at this time. Flu can be transmitted through these products.

At the time of this writing, there are news stories about cats who were given raw milk and subsequently died from avian flu. The risk is small, but there are so many excellent cheeses made from pasteurized milk that, in my opinion, it isn’t worth the risk.