— Shirley, Ohio It’s not just milk — there are many other foods that can interfere with antibiotics, as well as other drugs. In order for oral antibiotics to be effective, they must be absorbed from the gastrointestinal tract, make their way into the bloodstream, and be delivered to the infected area. Many factors influence the body’s ability to accomplish this feat, including the relative acidity of the stomach, the presence of fat or other nutrients in the stomach, and whether certain elements such as calcium are present. The classic family of antibiotics that cannot be taken with milk are the tetracyclines, because the calcium in the milk binds the antibiotic and prevents gut absorption. For most antibiotics, food results in either a decrease in absorption or has no effect. However, some antibiotics are actually better absorbed when taken with food, and it is recommended that others be taken while eating, because the food does not have a significant impact on absorption and may decrease any potential stomach upset from the drugs. It is very important to follow the directions on the prescription bottle, because pharmacists are the experts in these interactions. Not following directions may result in the antibiotic failing to cure the infection. Q2. My mom is 64 and has had multiple sclerosis for over 30 years. She is totally immobile and has been on a catheter for about one year. She has a problem with kidney stones and recurring urinary tract infections. Is there any way she could take some kind of antibiotic as a preventive measure to keep her from getting these infections so frequently? Your mother’s situation is complicated. Anyone with an indwelling catheter in the bladder will develop chronic colonization of the urinary tract by bacteria. There is no good way to eradicate such colonization. Furthermore, chronic use of antibiotics in such situations can lead to the development of resistant organisms, which can lead to more severe infections. A complicating factor is the presence of kidney stones. Some kidney stones are related to the presence of bacteria. Certain bacteria contain an enzyme that breaks down urea, a normal component of the urine. The breakdown product is ammonium, a compound that, in combination with magnesium and phosphate, forms stones. These are often called “infection stones” or “struvite stones.” Once these struvite stones form, they can be eradicated only by surgical treatment. Antibiotic therapy is not effective. Furthermore, until the stones are removed, there will always be an additional bacterial load in the urine. Your mother’s problem requires the input of a specialist. If you mother is not being cared for by a urologist, I suggest that you seek one out. Urologists are surgeons who treat both medical and surgical aspects of kidney stone disease and bladder infection and can work with you and your mother to develop a treatment plan. Learn more in the Everyday Health Healthy Living Center.
