Doxycycline (Oral)

Doxycycline is also under US brand names name, Adoxa CK, Adoxa, Adoxa Pak, Alodox, Adoxa TT, Doryx, Monodox, Oracea, Vibramycin Hycla, Periostat, Vibramycin Calcium, Vibramycin Monohydrate and Vibra-Tabs. It is used to treat a variety of bacterial infections that works by fighting bacteria in the body.


Doxycycline is used to treat bacterial infections in many different places of the body. It's also used in the treatment of abscesses or to treat pimples that are caused by adult acne, which is also known as rosacea.

Doxycycline delayed-release tablets are used to treat anthrax infection and prevent malaria after the possibility of being exposed and other issues that have been determined by a healthcare professional or your doctor.

Doxycycline belongs to a group class of medications known as tetracycline antibiotics. They work by preventing the growth of bacteria or killing bacteria. However, this medication will not work for flu, colds or other viral infections. This medication is only available via prescription from your doctor and is available in the following dosage form of power for suspension, tablet, capsule, delayed release tablet and syrup.

Condition(s) treated?

  • Relapsing fever
  • Infection due to the Microorganism Chlamydia Psittaci

Type of medicine

  • Oral tablet

Side effects

Along with its intended effects, the consumption of doxycycline can produce some unwanted side effects. Not all of these side effects may be present at once, but if they are present they may require medical attention.

Let your doctor know if you suffer from any of the following side effects whilst taking doxycycline.

Incidence not known

Some side effects that may occur with doxycycline, usually don't require medical attention. You usually find that these side effects begin to disappear as your body starts to adjust to the medication. If the side effects are persistent, then contact your local pharmacist or healthcare professional for advice on ways to prevent or reduce the side effects.

Incidence not known

  • Leg, back, or stomach pains

Remember you can report all side effects to FDA on 1-800-FDA-1088.


The final dose of all medications depend on the individual patient and will depend on a number of factors including, age, weight and height. Your previous medical history will also alter the dose, and any current and past medications you are on. You should let your doctor know if there are any medical conditions that run in your family history. Do not alter or change your dose without advice from your doctor.

For oral dosage forms (capsules, delayed-release tablets, suspension, syrup, tablets):

Adults: 100 milligrams every 12 hours on the first day, then 100 mg once daily or 50 - 100 mg every 12 hours.

Children older than eight years old who weigh 45 kg or less: Dose is based on individual weight and must be determined by your doctor. Typically the dose is 4.4 milligrams per kilogram of body weight per day and divided into two doses on the first day of treatment.

This should be followed by a dose of 2.2 mg per kg of body weight each day, taken as either a single dose or a dose divided into two separate doses on the following days.

Children up to the age of eight years old: Use is not recommended.

For the prevention of malaria:

Adults: 100 milligrams once a day. You should take the first dose one-two days before you enter the zone that is at risk of malaria. You need to continue taking the medication every day whilst in the area and for four weeks after you leave the malaria area.

Children older than 8 years old: Dose is based on individual body weight and will be decided by your doctor. The dose is usually 2 milligrams per kilo of your body weight daily. You should take the first dose one to two days before you enter the malaria zone and continue to take it each day and for four weeks after leaving the

For anthrax after possible exposure:

Children or adults who weigh 45 kilograms or more: 100 milligrams twice a day (taken every 12 hours) for 60 days.

Children weighing under 45 kg: This is based must be determined by your doctor by body weight. The dose is typically 2.2 milligrams per kilogram of body weight per day, twice a day for sixty days.


Drug interactions can cause unwanted and severe side effects and reduce the effectiveness of either drug. To reduce the risk of side effects, you should give your doctor a full list of all the medications you are currently taking as well as medications in the past. This list should include all prescription and non-prescription drugs, herbal products and vitamins. You should also let your doctor know of any medical conditions you currently suffer from.

There are over 300 drugs that can interact with doxycycline. Let your doctor know if you are taking any of the following drugs.

  • Magnesium aspartate

The use of this medication with any of the following medications is not recommended. Your doctor may decide to avoid treating you with this drug or alter some of the other medications you are taking.

  • Acitretin

The use of this medication with any of the following medications is not usually recommended, but in some cases, it may be necessary. If both medications are prescribed together then your doctor may alter the dose or the frequency of one or both medications.

  • Penicillin G Procaine

The use of this medication alongside doxycycline could increase your risk of some side effects, but in some cases, the treatment may be necessary. If both medications are prescribed together, then your doctor may alter the dose or frequency in which you use both medications.

  • Magnesium Trisilicate

Other medical conditions

The presence of other medical conditions could affect the use of this medication. You should inform your doctor or healthcare professional if you suffer from any of the following medical conditions:

  • Asthma Vibramycin┬« syrup contains sodium metabisulfite, which could cause allergic and life-threatening reactions in patients who suffer from this condition.



Let your doctor know if you've ever had any allergic reactions from this medication or any other medications. You should also tell your doctor if you suffer from any other allergies including to preservatives, dyes, animals or food.

Use in paediatric population

Doxycycline can slow down the growth of bones or cause permanent discoloration of the teeth. This medication should not be given to children under the age of eight (the only exception is the treatment of exposure to inhalational anthrax) unless it has been directed by the child's doctor.

Use in the geriatric population

Studies conducted to date have not indicated a geriatric-specific problem that could limit the effectiveness of doxycycline in the older population. However, elderly patients are more likely to have heart problems or kidney and liver problems which may require caution to be exercised and adjustments made in dose if necessary.

Use in pregnancy and breastfeeding

This drug is under FDA pregnancy category D. Taking this medication during pregnancy may affect bone and tooth development in the unborn child. If you take doxycycline during the last half of pregnancy, it can cause permanent tooth discoloration later on in the child's life. Let your doctor know if you are pregnant or if you become pregnant while using this medication.

This drug can make birth control pills less effective. You should ask your doctor about using a non-hormonal birth control (diaphragm, condom with spermicide) to prevent pregnancy.

With regards to breastfeeding, this drug can pass into breast milk and can affect tooth and bone development in a nursing baby. Don't use this medication while breastfeeding.

This medication can darken the color of your nails, skin, eyes, teeth, scars or gums. Speak with your doctor if you have any queries or questions.

Doxycycline can cause diarrhea, and sometimes it can be severe. It could occur two months or more after you stop taking this medication. Don't take any medication to treat diarrhea without first consulting with your doctor or a healthcare professional first. Diarrhea medications may make diarrhea last longer or make the condition more severe.

Birth control pills (containing estrogen) sometimes do not work as effectively when you are using doxycycline. To prevent yourself from falling pregnant, use other forms of birth control as well. These include a diaphragm, condoms or contraceptive jelly or foam.

Doxycycline can make your skin more sensitive to sunlight than normal. Exposure to sunlight, even for small periods of time, can cause redness, a skin rash, itching or other discoloration of the skin. It can also include severe sunburn. When you begin taking this medication:

  • Stay out of direct sunlight, especially between the hours of 10am and 3pm.
  • Wear protective clothing, including a sunglasses and a hat.
  • Apply a sunblock product that has an SPF number of at least 15. Some patients may need a higher SPF number, especially if they are fair. If you have any questions about this, speak with your doctor. You should apply sunblock on your lips to protect them.
  • Don't use a tanning bed, booth or sun lamp.
  • If you have a severe reaction from the sun, consult with your doctor.
  • This medication can cause intracranial hypertension. This is more likely to occur in women who are overweight, of childbearing age and have a history of intracranial hypertension. Inform your doctor immediately if you have blurred vision, a headache or changes in your vision.
  • Speak with your doctor immediately if you experience a rash, fever, tiredness or joint pain. These could be signs of an autoimmune syndrome where the body attacks itself.
  • You should not take antacids that contain calcium, aluminium, or magnesium, or any product that contains an iron supplement such as a mineral supplement or vitamin.
  • If you are using this medication to prevent malaria, you need to take extra measures to ensure you do not get bitten by mosquitoes. Use mosquito nets or screens, protective clothing and an insect repellent.
  • Before you have any medical tests, let your doctor know that you are taking this medication. The test results could be affected by this medication.
  • Don't take other medications unless they have been previously discussed with your doctor.

Proper use

Take this medication exactly as you have been directed by a healthcare professional or your doctor. Don't take more or less medication, or take it more often or take it for a longer amount of time. If you do this it could increase your chance of side effects.

This medication comes with patient instructions. You should follow and read them carefully. If you have any questions, you should contact your doctor.

  • If you are using delayed-release tablets:

It may be taken with milk or food. If it upsets your stomach, you can break the tablets. Hold the tablet between your index fingers and thumb to the appropriate separation line. Then, apply pressure to snap the segments of the tablet apart. Don't use this tablet if it doesn't break on the scored lines.

You can also take this medication by sprinkling the equally broken tablets onto soft food that is cold. The mixture should be swallowed immediately and followed with a glass of cold water to ensure that the pellets are swallowed completely. Don't store the mixture for later use.

Swallow the capsule whole. Don't crush, break, chew or open it.

Drink plenty of fluids to avoid ulceration or throat irritation.


This medication needs to be stored in a closed container at room temperature. You should keep it away from moisture, heat and direct light. Do not let medication freeze. Keep out of the reach of young children. Don't keep medication that is out of date or no longer needed. You should seek advice from your healthcare professional about ways to dispose of medications you are finished with.


When used correctly, doxycycline is successful in the treatment of many bacterial infections and in the prevention of malaria. Due to the large number of interactions, it is important that you give your doctor a complete list of all the medications you are currently taking.

If your symptoms don't begin to improve within a few days, or if your symptoms become worse, you should consult your doctor as your dose may need to be altered. Do not alter or change your dose without the advice from your doctor.

Do not use this medication whilst pregnant or breastfeeding. This medication can reduce the effectiveness of birth control pills, so you should take extra precautions to ensure you do not fall pregnant whilst taking this medication. Caution should be exercised in the use of this medication in children under eight years old.