Doxycycline Antibiotics

What is Doxycycline?

Doxycycline is an antibiotic used to treat a broad range of bacterial infections, including chlamydia, and is also used as an antimalarial for use when travelling.

How does Doxycycline work?

Doxycycline is an antibiotic known as a tetracycline. It works by stopping growth and replication of bacteria, preventing the spread of infection and allowing the body’s immune system to kill off the remaining bacteria.

How effective is Doxycycline?

The standard seven-day course of Doxycycline has been shown to cure chlamydia infection in 98% of cases. If your symptoms persist after you have completed treatment, it is important to see your doctor who may need to test you again. As with all antibiotics, bacteria can develop resistance, which may mean the treatment does not work as well. You may require a longer course of Doxycycline, or a different antibiotic if the initial treatment has not worked.

How to take Doxycycline for Chlamydia?

You should take Doxycycline as instructed by your doctor. The usual dose for treatment of chlamydia is 100mg twice daily for 7 days. 

Each tablet should be swallowed whole with a glass of water while sitting or standing, at around the same time every day. Try not to lie down for 30 minutes after taking this medication, as it may cause irritation to the oesophagus. If you find that the medication causes nausea or indigestion, take the tablets with food.

Doxycycline dosage

You should take Doxycycline according to the prescribing doctor’s instructions. The usual dose for treatment of chlamydia is 100mg twice per day for 7 days. A longer duration of therapy may be indicated in specific circumstances.

How long does Doxycycline take to work?

Doxycycline is rapidly absorbed and begins to stop bacterial reproduction right away. You may notice an improvement in symptoms within a few days. You should complete the entire course of Doxycycline as directed by your doctor, even if your symptoms have resolved before you have finished the course. Not completing a course of antibiotics, can contribute to antibiotic resistance, making bacterial infections harder to treat.

Should you take Doxycycline with food?

Doxycycline can be taken with or without food, and should always be taken with a full glass of water. If you find taking the tablets makes you feel nauseous, it is recommended to take Doxycycline with a meal or directly after.

What if I forget to take a dose?

Doxycycline should be taken at the same time/s each day. If you miss a tablet, take it as soon as you remember, however, if it is only a few hours until your next dose, skip the missed dose. Do not take a ‘double dose’ to make up for a missed dose.

Do I need to finish the course, even if my symptoms clear up?

You should always finish a course of antibiotics, even if your symptoms clear up before you have completed the course. Failure to finish the course may result in the infection persisting or antibiotic resistance. Antibiotic resistance is where bacteria adapt to protect themselves from certain antibiotics, this resistance makes it harder to treat the infection.

Doxycycline side effects

Like all medications, Doxycycline can cause side effects in some patients. 

Common side effects include:

• Nausea, loss of appetite or vomiting
• Headaches
• Light sensitivity (photosensitivity)
• Irritation to the gastrointestinal tract (symptoms include a sore mouth, heartburn, nausea)

Serious side effects:
If you experience any of the following, stop taking your medicine and seek medical attention immediately:

• Symptoms of an allergic reaction, including wheezing or difficulty breathing, chest pain or tightness, swelling of the face, lips, tongue, throat, hands or feet, fever, rash, or collapse
• Unexplained bleeding
• Symptoms of DRESS (Drug Reaction with Eosinophilia and Systemic Symptoms), such as fever, swollen lymph nodes or skin rash
• Upset stomach, severe abdominal pain, loss of appetite, severe, persistent or bloody diarrhoea
• Very severe headache which may be associated with visual disturbances such as blurred vision, double vision or loss of vision
• Severe skin reactions involving irregular, circular patches, flushing, fever, blisters, ulcers, reddening, peeling and swelling, which could indicate erythema multiforme, Stevens-Johnson syndrome or toxic epidermal necrolysis
• A ringing or buzzing noise in the ear (tinnitus)

Other side effects:
If you experience any of the following side effects, seek advice from your doctor as soon as possible:

• Fever or chills
• Skin rash
• Sensitivity to sunlight
• Nausea and vomiting
• Heartburn
• Pain or swallowing difficulty 
• Excessive tiredness or weakness
• Easy bruising
• Headache
• Aching joints or muscles
• Unusual or rapid heartbeat
• Low blood pressure or fainting
• Yellowing of the skin or eyes (jaundice)
• Darkening of the urine and/or pale faeces
• Diarrhoea
• Abdominal pain
• Soreness or itching of the genital or rectal area

This is not an exhaustive list of side effects, please check the package insert for more information.

Contraindications

You should not use Doxycycline if you are allergic to Doxycycline or any other tetracycline antibiotic. You should not use this medication if you are pregnant, planning to become pregnant, or breastfeeding.

If you are taking any other medication, or if you have any other health conditions, particularly kidney or liver problems, myasthenia gravis, systemic lupus erythematosus (SLE) or porphyria you should inform the prescribing doctor as this medication may not be suitable. 

You should inform the prescribing doctor if you are going to be exposed to strong sunlight or UV light (including sunbeds) or if you have previously experienced side effects such as diarrhoea when taking antibiotics.

Drug interactions

You should inform the prescribing doctor if you are taking, have taken or are planning on taking any other medications, including over the counter (non-prescription) medications, vitamins, herbal remedies and recreational drugs. 

Doxycycline may interact with other medications. It is particularly important you tell your doctor if you are taking any of the following: 

• Antacids and other medicines containing aluminium, calcium, magnesium, iron, bismuth or zinc salts
• Penicillin or any other antibiotic
• Rifampicin
• Anticoagulants such as warfarin
• Anti-epileptic drugs such as barbiturates, carbamazepine and phenytoin
• Ciclosporin
• Isotretinoin or other systemic retinoids
• Methoxyflurane
• Quinapril
• Kaolin
• Sucralfate
• Ergotamine or methysergide
• Oral typhoid vaccine

This is not an exhaustive list, so make sure you inform your doctor of any medications, alternative medicines, supplements, recreational drugs or over the counter treatments that you are taking. 
 

How to cope with Doxycycline side effects?

Common side effects of Doxycycline include headaches, nausea, vomiting and sensitivity to sunlight. Some measures you can take to manage these side effects include:

• Drinking plenty of water and keeping well rested if you feel unwell
• Taking painkillers such as paracetamol and ibuprofen to ease headaches
• If nausea is an issue, taking your dose of Doxycycline with or after a meal
• If you are vomiting, eating small simple meals and staying well hydrated
• Speaking to your doctor if vomiting is preventing you from taking your medication
• Making sure to use plenty of sunscreen when going out in the sun, and ensuring skin is covered in peak sunlight

Will Doxycycline affect my fertility?

There is no evidence to suggest that Doxycycline has an effect on male or female fertility.

Will Doxycycline affect my contraception?

Doxycycline does not affect contraceptives. Speak to your doctor for further advice.

Doxycycline and alcohol

You should not drink alcohol while taking Doxycycline, as this may reduce the effectiveness of the medication.

Doxycycline and pregnancy

Doxycycline should not be taken if you are pregnant, planning to become pregnant, or breastfeeding. Speak to your doctor for further advice.

What are the uses of Doxycycline?

Doxycycline is a broad-spectrum antibiotic and can be used to treat a number of bacterial infections. Common uses of Doxycycline include the treatment of acne and rosacea, chest infections, skin infections, STIs, and for the prevention of malaria in travellers.

Will Doxycycline stain my teeth?

Doxycycline should be avoided during periods of tooth development, such as pregnancy and in children under the age of 8. Doxycycline has been shown to cause permanent discolouration of the teeth.

Will Doxycycline give me thrush?

Doxycycline is a broad-spectrum antibiotic, meaning it suppresses the reproduction of several different kinds of bacteria, some of which reside naturally in the body. This can lead to an overgrowth of other bacteria, or of yeast infections. Thrush can therefore occur as a result of Doxycycline use. Speak to your doctor if you experience any symptoms of thrush after you have completed the course of Doxycycline.

Is Doxycycline an antibiotic?

Yes. Doxycycline is a tetracycline antibiotic which is used to treat a broad range of bacterial infections.

Active ingredients

The active ingredient in Doxycycline is doxycycline hyclate.

Inactive ingredients

The inactive ingredients in Doxycycline tablets may include: sucrose, maize starch, crospovidone, basic butylated methacrylate copolymer (Eudragit E100) and purified talc.

Please note: Different brands may contain different inactive ingredients

Which ingredients can cause an allergic reaction?

Doxycycline has been known to cause mild allergic reactions in users with cases of 1 in 100. However, a severe allergic reaction presenting as facial/lip swelling, wheezing, chest tightness and difficulty breathing, are rare. A severe allergic reaction is a medical emergency and you should seek medical attention or call 999 right away if you notice any of the symptoms mentioned above.