Common uses

Doxycycline is used for many different bacterial infections. In gastroenterology it is often used to prevent or treat travelers diarrhea which is caused by an E. Coli bacterial strain.

Before using

Do not use this medication if you are allergic to doxycycline, or to similar medicines such as demeclocycline (Declomycin), minocycline (Dynacin, Minocin, Solodyn, Vectrin), or tetracycline (Brodspec, Panmycin, Sumycin, Tetracap). Before taking doxycycline, tell your doctor if you have liver or kidney disease. You may not be able to take doxycycline, or you may need a dose adjustment or special tests during treatment.
If you are using doxycycline to treat gonorrhea, your doctor may test you to make sure you do not also have syphilis, another sexually transmitted disease.
Do not use doxycycline syrup (Vibramycin) without first talking to your doctor if you have asthma or are allergic to sulfites.
FDA pregnancy category D. This medication can cause harm to an unborn baby, including permanent discoloration of the teeth later in life. Do not use doxycycline without your doctor's consent if you are pregnant. Doxycycline passes into breast milk and may affect bone and tooth development in a nursing infant. Do not take this medication without first talking to your doctor if you are breast-feeding a baby. Children younger than 8 years old should not take doxycycline.

Directions

Follow your physician's instructions carefully. Take doxycycline with a full glass of water or other liquid to avoid irritating your esophagus (food pipe). Doxycycline can be taken with or without food. If it upsets your stomach, you may want to take it with a glass of milk or after you have eaten. Take dosages at approximately the same time each day. As with all antibiotics, be sure to take the full prescribed dose. Doxycycline should be stored at room temperature away from light and excessive heat. Keep all medications away from children. Never share your medications with anyone else.


Cautions

At times, a drug may have a different or enhanced effect when other diseases are present. At other times, the drug may worsen or effect another disease.
With this drug, the following disorders may be a problem:
• severe chronic liver disease (cirrhosis)
• systemic lupus erythematosus
• Steven's-Johnson Syndrome
Most females now know that, if possible, no drug, including alcohol, should be taken during pregnancy or lactation. The potential danger, of course, is an injury to the baby. However, some drugs are much safer than others in this regard. So, the FDA has a grading system for each drug which reflects what is known medically. It ranks drugs from A, where medical studies show no evidence for danger to the fetus or mother, to B, C, D and X, where the medical evidence indicates that the risk to the fetus outweighs any benefit to the mother. Doxycycline is ranked D. Always consult your physician before taking any drug during or when planning pregnancy.

• Doxycycline is not recommended in children under 8 or pregnant women because it can cause a permanent discoloration of the teeth (yellow-gray-brown).
• Doxycycline may cause photosensitivity making you more prone to a sunburn.
• Never take outdated doxycycline because it may be toxic to the kidneys.
• Troublesome and persistent diarrhea can develop in some individuals. If diarrhea develops and persists for more than 24 hours, discontinue the medication and contact your physician.
• Prolonged or repeated use of antibiotics may result in fungal infection. These are usually due to yeast organisms and occur in the mouth, intestinal tract and vagina.

Possible side effects

Adverse reactions can occur with any drug, even over-the-counter medications. Some of these are mild such as a stomach upset, which may be avoided by taking the medication with food. Minor reactions may go away on their own but if they persist, contact the physician. For major reactions, the patient should contact the physician immediately.
For doxycycline, the following are the observed side effects:
Minor:
• discoloration and soreness of tongue
• nausea
• stomach irritation
• vomiting
• diarrhea
• itching of genital or rectal area
Major:
• yellow color to skin or eyes
• swollen joints or lymph nodes


If you take too much

Seek emergency medical attention if you think you have used too much of this medicine. Overdose symptoms may include nausea, vomiting, and diarrhea.

Additional information

Avoid meats, iron-fortified cereals and iron supplements for 2 hours before and after taking this drug. There are no interactions with alcohol, but combining doxycycline and alcohol should be avoided if you have active liver disease.

People who have known allergies or asthma may be at an increased risk for a reaction from any new medication. The physician should always know a patient's allergy history. Signs of an allergic reaction are skin rash, hives and itching. Of course, a person should not take doxycycline if there has been a previous reaction to this or a similar drug such as tetracycline.

Birth control pills may not be as effective while you are taking doxycycline. A supplemental form of birth control is recommended during antibiotic therapy.

Drug interactions

An interaction generally means that one drug may increase or decrease the effect of another drug. Also, the more medications a person takes, the more likely there will be a drug interaction.
Interactions with this drug may occur with the following:
• blood thinners (Coumadin)
• digoxin (Lanoxin)
• lithium (Eskalith)
• carbamazepine (Tegretol)
• phenytoin (Dilantin)
• cimetidine (Tagamet)
• barbiturates (phenobarbital)
• birth control pills
• antacids
• penicillins
• iron, mineral or calcium supplements