Tetracyclines are used to treat infections and to help control acne. Doxycycline also may be used for other problems as determined by your doctor. Tetracyclines will not work for colds, flu, or other virus infections.
In deciding to use a medicine, the risks of taking the medicine must be weighed against the good it will do. This is a decision you and your doctor will make. For tetracyclines, the following should be considered:
Allergies-Tell your doctor if you have ever had any unusual or allergic reaction to any of the tetracyclines or combination medicines containing a tetracycline. Also tell your health care professional if you are allergic to any other substances, such as foods, preservatives, or dyes. In addition, if you are going to be given oxytetracycline by injection, tell your doctor if you have ever had an unusual or allergic reaction to "caine-type" anesthetics (e.g., lidocaine).
Pregnancy-Use is not recommended during the last half of pregnancy. If tetracyclines are taken during that time, they may cause the unborn infant's teeth to become discolored and may slow down the growth of the infant's teeth and bones. In addition, liver problems may occur in pregnant women, especially those receiving high doses by injection into a vein.
Breast-feeding-Use is not recommended since tetracyclines pass into breast milk. They may cause the nursing baby's teeth to become discolored and may slow down the growth of the baby's teeth and bones. They may also increase the sensitivity of nursing babies' skin to sunlight and cause fungus infections of the mouth and vagina. In addition, minocycline may cause dizziness, light-headedness, or unsteadiness in nursing babies.
Children-Tetracyclines may cause permanent discoloration of teeth and slow down the growth of bones. These medicines should not be given to children 8 years of age and younger unless directed by the child's doctor.
Older adults-Many medicines have not been studied specifically in older people. Therefore, it may not be known whether they work exactly the same way they do in younger adults or if they cause different side effects or problems in older people. There is no specific information comparing use of tetracyclines in the elderly with use in other age groups.
Other medicines-Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. When you are taking tetracyclines, it is especially important that your health care professional know if you are taking any of the following:
Other medical problems-The presence of other medical problems may affect the use of tetracyclines. Make sure you tell your doctor if you have any other medical problems, especially:
Do not give tetracyclines to infants or children 8 years of age and younger unless directed by your doctor. Tetracyclines may cause permanently discolored teeth and other problems in patients in these age groups.
Tetracyclines should be taken with a full glass (8 ounces) of water to prevent irritation of the esophagus (tube between the throat and stomach) or stomach. In addition, most tetracyclines (except doxycycline and minocycline) are best taken on an empty stomach (either 1 hour before or 2 hours after meals). However, if this medicine upsets your stomach, your doctor may want you to take it with food.
Do not take milk, milk formulas, or other dairy products within 1 to 2 hours of the time you take tetracyclines (except doxycycline and minocycline) by mouth . They may keep this medicine from working properly.
If this medicine has changed color or tastes or looks different, has become outdated (old), or has been stored incorrectly (too warm or too damp area or place), do not use it . To do so may cause serious side effects . Throw away the medicine. If you have any questions about this, check with your health care professional.
For patients taking doxycycline :
To help clear up your infection completely, keep taking this medicine for the full time of treatment , even if you begin to feel better after a few days. If you stop taking this medicine too soon, your symptoms may return.
This medicine works best when there is a constant amount in the blood or urine. To help keep the amount constant, do not miss any doses. Also, it is best to take the doses at evenly spaced times day and night . For example, if you are to take four doses a day, the doses should be spaced about 6 hours apart. If this interferes with your sleep or other daily activities, or if you need help in planning the best times to take your medicine, check with your health care professional.
Dosing-The dose of these medicines will be different for different patients. Follow your doctor's orders or the directions on the label . The following information includes only the average doses of these medicines. If your dose is different, do not change it unless your doctor tells you to do so.
For doxycycline For oral dosage forms (capsules, suspension, and tablets):
If your symptoms do not improve within a few days (or a few weeks or months for acne patients), or if they become worse, check with your doctor.
Oral contraceptives (birth control pills) containing estrogen may not work properly if you take them while you are taking tetracyclines. Unplanned pregnancies may occur. You should use a different or additional means of birth control while you are taking tetracyclines . If you have any questions about this, check with your health care professional.
Before having surgery (including dental surgery) with a general anesthetic, tell the medical doctor or dentist in charge that you are taking a tetracycline. This does not apply to doxycycline, however.
Tetracyclines may cause your skin to be more sensitive to sunlight than it is normally. Exposure to sunlight, even for brief periods of time, may cause a skin rash, itching, redness or other discoloration of the skin, or a severe sunburn. When you begin taking this medicine:
You may still be more sensitive to sunlight or sunlamps for 2 weeks to several months or more after stopping this medicine. If you have a severe reaction, check with your doctor .
Once a medicine has been approved for marketing for a certain use, experience may show that it is also useful for other medical problems. Although these uses are not included in product labeling, tetracyclines are used in certain patients with the following medical conditions: