Doxycycline belongs to the class of medications called tetracyclines. Although in higher strengths, it is an antibiotic that is used to treat certain types of bacterial infections, this form is only designed to treat the pimples and bumps caused by rosacea. Doxycycline works by reducing the natural chemicals in the body that cause the skin inflammation that occurs during a rosacea flare-up.

This medication may be available under multiple brand names and/or in several different forms. Any specific brand name of this medication may not be available in all of the forms or approved for all of the conditions discussed here. As well, some forms of this medication may not be used for all of the conditions discussed here.

Your doctor may have suggested this medication for conditions other than those listed in these drug information articles. If you have not discussed this with your doctor or are not sure why you are taking this medication, speak to your doctor. Do not stop taking this medication without consulting your doctor.

Do not give this medication to anyone else, even if they have the same symptoms as you do. It can be harmful for people to take this medication if their doctor has not prescribed it.

The recommended adult dose of this medication is 40 mg taken once daily, in the morning. It should be taken on an empty stomach, at least 1 hour before eating or 2 hours after a meal. To reduce irritation to the esophagus (the tube leading to the stomach), swallow the capsule with plenty of fluid.

Many things can affect the dose of medication that a person needs, such as body weight, other medical conditions, and other medications. If your doctor has recommended a dose different from the ones listed here, do not change the way that you are taking the medication without consulting your doctor.

It is important that this medication be taken exactly as prescribed by your doctor. If you miss a dose, skip the missed dose and continue with your regular dosing schedule. Do not take a double dose to make up for a missed one. If you are not sure what to do after missing a dose, contact your doctor or pharmacist for advice.

Store this medication at room temperature, protect it from light and moisture, and keep it out of the reach of children. This medication should be stored in its original package to protect it from light.

40 mg
Each beige, opaque, hard gelatin capsule, imprinted with "GLD 40" contains two types of beads that together provide a dose of 40 mg of doxycycline (as doxycycline monohydrate). Nonmedicinal ingredients: hypromellose, methacrylic acid copolymer, opadry beige, sugar spheres, talc, and triethyl citrate.

Do not take doxycycline if you:

• are allergic to doxycycline or any ingredients of the medication
• are allergic to other tetracycline antibiotics
• are a woman in the second or third trimester of pregnancy
• are breastfeeding
• have myasthenia gravis

Do not give this medication to children under 8 years of age.

Many medications can cause side effects. A side effect is an unwanted response to a medication when it is taken in normal doses. Side effects can be mild or severe, temporary or permanent.

The side effects listed below are not experienced by everyone who takes this medication. If you are concerned about side effects, discuss the risks and benefits of this medication with your doctor.

The following side effects have been reported by at least 1% of people taking this medication. Many of these side effects can be managed, and some may go away on their own over time.

Contact your doctor if you experience these side effects and they are severe or bothersome. Your pharmacist may be able to advise you on managing side effects.

• abdominal pain
• diarrhea
• headache
• nausea
• sore nose or throat

Although most of the side effects listed below don't happen very often, they could lead to serious problems if you do not check with your doctor or seek medical attention.

Check with your doctor as soon as possible if any of the following side effects occur:

• discolouration of skin, scars, teeth, or gums
• increased blood pressure
• severe or unusual sunburn
• signs of bowel inflammation (e.g., fever that appears after starting the medication, watery and severe diarrhea [may also be bloody])
• sinus infection

Stop taking the medication and seek immediate medical attention if any of the following occur:

• signs of increased blood pressure in the brain (e.g., severe headache, migraine, or dizziness)
• signs of a serious allergic reaction (e.g., abdominal cramps, difficulty breathing, nausea and vomiting, or swelling of the face and throat)

Some people may experience side effects other than those listed. Check with your doctor if you notice any symptom that worries you while you are taking this medication.

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.

Bacterial resistance: This form of doxycycline is only intended to treat rosacea. It should not be used to treat active infections. Misuse of an antibiotic such as doxycycline may lead to the growth of resistant bacteria that will not be killed by the antibiotic. If this happens, the antibiotic may not work for you in the future.

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.

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.

High blood pressure in the brain: Doxycycline may increase the risk of high blood pressure in the brain. This may appear as a bulging soft spot on the head of infants. Contact your doctor right away if you experience blurred vision, double vision, and headache.

Immune system problems: Rarely, people taking medications in the same family as doxycycline may develop symptoms similar to the symptoms of lupus (rash on the cheeks or other body areas; sun sensitivity; joint or muscle pain; fatigue; chest pain; shortness of breath; or swelling of the feet, ankles, or legs). Contact your doctor if you develop these symptoms.

Liver function: People with liver disease may have a higher risk of side effects from this medication. If you have liver disease or reduced liver function, 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.

Myasthenia gravis: Myasthenia gravis is a condition that causes specific muscle weakness. Doxycycline may make the symptoms of this illness worse. If you have myasthenia gravis, 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.

Other infections: Treatment with any tetracycline may allow normal fungus or types of bacteria not killed by the antibiotic to overgrow, causing unwanted infections such as yeast infections, which may cause vaginal itching and irritation. Women may prevent yeast infections by eating yogurt daily while taking this antibiotic. Talk to your doctor if you have any concerns

Stomach problems: People taking this medication may develop diarrhea caused by an infection with the bacteria C. difficile. If you have loose, watery, and bloody bowel movements, with or without fever or stomach cramps after taking doxycycline, get medical attention as soon as possible. Diarrhea caused by C. difficile infection can lead to serious health problems if it is not properly treated.

Stomach surgery: This medication is not recommended for use by people who have had certain types of stomach surgery such as gastric bypass surgery or gastrectomy (removal of part or all of the stomach).

Sunburn: An exaggerated sunburn reaction may occur for some people taking tetracyclines, including doxycycline. Avoid exposure to excessive sunlight, including sunlamps and tanning beds, and use sunblock with minimum SPF 30. Stop taking doxycycline at the first sign of skin redness.

Pregnancy: Like other tetracycline antibiotics, doxycycline may cause harm to the developing baby if this medication is taken during pregnancy. This medication 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 passes into breast milk and causes discolouration of the teeth and reduced bone growth in a breast-feeding infant if it is taken by the mother while still breast-feeding. Due to the adverse effects on the developing infant, this medication should not be used by women who are breast-feeding.

Children: The use of doxycycline during tooth development (from the last trimester of pregnancy to the age of 8 years) may cause permanent discoloration of the teeth (yellow-grey-brown). Though more commonly associated with long-term use of tetracyclines, this effect has also been known to occur after taking the medication for a short time.

The safety and effectiveness of using this medication have not been established for children under 8 years of age.

There may be an interaction between doxycycline and any of the following:

• antacids (e.g., aluminum hydroxide, calcium carbonate, magnesium hydroxide)
• aripiprazole
• aspirin
• barbiturates (e.g., butalbital, pentobarbital, phenobarbital)
• BCG
• birth control pills
• bismuth subsalicylate
• calcium supplements
• carbamazepine
• cholera vaccine
• cholestyramine
• colestipol
• iron supplements
• lanthanum
• lithium
• magnesium supplements
• methotrexate
• multivitamins/minerals with vitamins A, D, and E
• penicillin antibiotics (e.g., amoxicillin, cloxacillin, penicillin)
• phenytoin
• pimozide
• porfimer
• primidone
• proton pump inhibitors (e.g., lansoprazole, omeprazole)
• quinapril
• retinoic acid derivatives (e.g., alitretinoin, isotretinoin, tretinoin)
• rifampin
• rocuronium
• sodium picosulfate
• sucralfate
• typhoid vaccine
• warfarin

If you are taking any of these medications, speak with your doctor or pharmacist. Depending on your specific circumstances, your doctor may want you to:

• stop taking one of the medications,
• change one of the medications to another,
• change how you are taking one or both of the medications, or
• leave everything as is.

An interaction between two medications does not always mean that you must stop taking one of them. Speak to your doctor about how any drug interactions are being managed or should be managed.

Medications other than those listed above may interact with this medication. Tell your doctor or prescriber about all prescription, over-the-counter (non-prescription), and herbal medications you are taking. Also tell them about any supplements you take. Since caffeine, alcohol, the nicotine from cigarettes, or street drugs can affect the action of many medications, you should let your prescriber know if you use them.