Before you begin using a medication, be sure to inform your doctor of any medical conditions or allergies you may have, any medications you are taking, whether you are pregnant or breast-feeding, and any other significant facts about your health. These factors may affect how you should use this medication.
Birth control: Some antibiotics may decrease the effectiveness of birth control pills. Ask your doctor if you should be using more than one method of birth control while you are taking this medication.
High blood pressure in the brain: Doxycycline may increase the risk of high blood pressure in the brain. Contact your doctor right away if you experience blurred vision, double vision, and headache.
Esophagus problems: People taking doxycycline have experienced ulcers and injury to their esophagus. To help prevent this, take doxycycline with a full glass of water while standing or sitting upright. Do not lie down for at least 1 to 2 hours after taking the medication.
Infection: This medication may cause an overgrowth of certain bacteria and fungi. If you experience frequent yeast infections in the mouth (thrush), discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.
The safety and effectiveness of using this medication for people with oral candidiasis (thrush) have not been established. If you develop symptoms of infection (e.g., fever, chills) while taking this medication, contact your doctor.
Stomach problems: People taking this medication may develop diarrhea caused by an infection with C. difficile bacteria. Get medical attention as soon as possible if you have loose, watery, and bloody bowel movements, with or without fever or stomach cramps, after taking doxycycline. Diarrhea caused by C. difficile infection can lead to serious health problems if it is not properly treated.
Sun sensitivity: This medication may make your skin more sensitive to the sun. Avoid excessive sun exposure, including sun beds and sun lamps, while taking this medication. If you cannot avoid sun exposure, use sunscreen and protective clothing. Stop
taking this medication and contact your doctor if you get a sunburn.
Tooth development: Using this medication during tooth development (e.g., the last half of pregnancy, infancy, or childhood up to the age of 8 years) may cause a permanent yellow-grey-brown discoloration of the teeth. This medication should not be used during pregnancy, breast-feeding, or for infants and children less than 8 years of age unless the benefits outweigh the risks.
Pregnancy: Doxycycline can cause birth defects to the unborn baby if it is taken during pregnancy. It should not be used during pregnancy unless the benefits outweigh the risks. If you become pregnant while taking this medication,
contact your doctor immediately.
Breast-feeding: This medication should not be used by breast-feeding women unless the benefits outweigh the risks. If you are a breast-feeding mother and are taking doxycycline, it may affect your baby. Talk to your doctor about whether you should
Children: The safety and effectiveness of using this medication have not been established for children less than 8 years of age.