TETRACYCLINES

Tetracyclines are rarely the antibiotics of choice to treat bacterial infections that are common in older adults. In general, tetracyclines are used to treat such infections as urethritis (inflammation of the urinary tract), prostate infections, pelvic inflammatory disease, acne, Rocky Mountain spotted fever, recurrent bronchitis in people with chronic lung disease, “walking” pneumonia, and other miscellaneous infections.[1]

Considerations When Prescribing for Older Adults

Since a decrease in kidney function is one of the normal changes associated with the aging process, tetracyclines must be used with this in mind. With the exception of doxycycline, these drugs should not be used for someone with impaired kidney function, as they can damage the kidneys further. Tetracyclines also can cause liver damage. This is more likely to happen when they are injected into the blood (intravenously) in people who already have liver or kidney impairment.[2]

Dosage Forms, Uses, and Effects

The oral forms—tablet, capsule, suspension—should be taken with a full glass (eight ounces) of water. The last dose of the day should be taken at least an hour before bedtime.[3] Esophageal ulcers (irritation of the esophagus, the tube leading from the throat to the stomach) have occurred in people who have taken doxycycline at bedtime with insufficient water to wash it down. Liquid forms should be shaken well before use. Do not freeze them. Try to take your doses at evenly spaced times during the day and night so that the amount of drug in your body will stay constant. If you miss a dose, take it as soon as possible. If it is almost time for the next dose and you are supposed to take your medicine

• once a day, space missed dose and next dose about 12 hours apart.
• twice a day, space missed dose and next dose about six hours apart.
• three or more times a day, space missed dose and next dose about three hours apart or double the next dose.

Go back to your regular schedule after following the instructions above.

The injected forms should only be used when the oral forms are not adequate or not tolerated, as they are very painful. The intravenous forms should be used only when the oral forms are not appropriate, as severe vein inflammation or clotting commonly occurs.[4]

Tetracyclines applied externally as ointments or creams are of little value except for treatment of some eye infections and possibly some skin conditions. Two types of eye (ophthalmic) preparations are available—ointment and drops. (See directions on applying eye preparations.)

Sometimes when tetracyclines are used, microbes that are not killed by these drugs cause infection. An example is candidiasis, a fungal infection. (Some of its symptoms are sore mouth and tongue and itching in the genital or rectal area.) Candidiasis in the mouth is fairly common in older adults who wear dentures.

Tell your doctor that you take a tetracycline before you have any tests done. These drugs may interfere with your urine test results. Talk to your doctor before you change your diet or any medication.