1. About doxycycline
Doxycycline is an antibiotic.
It can also be used to prevent malaria if you're travelling abroad.
Doxycycline is available on prescription. It comes as capsules.
2. Key facts
- For most infections, you'll start to feel better in a few days but it is important to finish the course of medicine.
- The most common side effects of doxycycline are headaches, feeling or being sick. It can also make your skin sensitive to the sun.
- Doxycycline can affect growing teeth so it's not prescribed for children under 12 years old or given to pregnant and breastfeeding women.
- Do not drink alcohol while taking doxycycline. There are also some common medicines you should not mix with it.
- Doxycycline can also be called by the brand name Vibramycin-D.
3. Who can and can't take doxycycline
Doxycycline can be taken by adults and children over 12 years old. Doxycycline is not usually recommended in pregnancy or when breastfeeding.
It isn't suitable for some people. To make sure this medicine is safe for you, tell your doctor if you have:
4. How and when to take it
Your dose of doxycycline depends on why you are taking it.
The usual dose is 100mg to 200mg once or twice a day. If you're taking doxycycline more than once a day, try to space your doses evenly throughout the day. If you take it twice a day, this could be first thing in the morning, and in the evening.
For preventing malaria, you'll take 100mg once a day, usually in the morning. You should start taking doxycycline 1 or 2 days before going to an area where there is malaria. Carry on for 4 weeks after leaving the area. Check with your doctor or pharmacist that doxycycline is the best medicine to prevent malaria in the country you are travelling to.
Carry on taking doxycycline until you've completed the course, even if you feel better. If you stop your treatment early, the infection could come back - or you may no longer be protected against malaria.
How to take it
Always swallow your doxycycline capsule whole and have it with a full glass of water (a medium sized glass - 200ml).
You can take this medicine with or without food. However you're less likely to feel sick if you have it with food.
It's important to take doxycycline while you're in an upright position. You can be sitting, standing or walking. This will stop the medicine irritating your food pipe or stomach.
What if I forget to take it?
If you forget to take a dose, take it as soon as you remember, unless it's nearly time for your next dose. In this case, just leave out the missed dose and take your next dose as normal.
Never take 2 doses at the same time. Never take an extra dose to make up for a forgotten one.
If you often forget doses, it may help to set an alarm to remind you. You could also ask your pharmacist for advice on other ways to remember your medicines.
What if I take too much?
Accidentally taking an extra dose of doxycycline is unlikely to harm you.
Speak to your pharmacist or doctor if you're worried or you take more than 1 extra dose.
5. Side effects
Like all medicines, doxycycline can cause side effects, although not everyone gets them.
Common side effects
These common side effects happen in around 1 in 10 people. Keep taking the medicine, but talk to your doctor or pharmacist if these side effects bother you or don't go away:
- feeling or being sick (nausea or vomiting)
- being sensitive to sunlight
Serious side effects
Serious side effects are rare and happen in less than 1 in 1,000 people.
Call a doctor straight away if you get:
- bruising or bleeding you can't explain (including nosebleeds), a sore throat, a high temperature (38C or above) and you feel tired or generally unwell - these can be signs of blood problems
- diarrhoea (possibly with stomach cramps) that contains blood or mucus - if you have severe diarrhoea that lasts longer than 4 days you should also speak to a doctor
- ringing or buzzing in your ears
- pale poo with dark pee, yellow skin or the whites of your eyes go yellow - this could be a sign of liver problems
- joint or muscle pain that has started since you began taking doxycycline
- severe headaches, vomiting and problems with your vision - these could be signs of pressure around your brain (intracranial hypertension)
- a fingernail coming away from its base - this could be a reaction to sunlight called photo-onycholysis
- a sore or swollen mouth, lips or tongue
- severe pain in your stomach, with or without bloody diarrhoea, nausea and vomiting - these can be signs of pancreatitis
- difficulty or pain when you swallow, a sore throat, acid reflux, a smaller appetite or chest pain which gets worse when you eat - these could be signs of an inflamed food pipe (oesophagitis) or oesophageal ulcer
Serious allergic reaction
Allergic reactions to doxycycline are common and occur in more than 1 in 100 people.
In rare cases, doxycycline can cause a serious allergic reaction anaphylaxis.
Urgent advice: Contact a doctor straight away if:
- you get a skin rash that may include itchy, red, swollen, blistered or peeling skin
- you're wheezing
- you get tightness in the chest or throat
- you have trouble breathing or talking
- your mouth, face, lips, tongue or throat start swelling
These are warning signs of a serious allergic reaction. A serious allergic reaction is an emergency.
These are not all the side effects of doxycycline. For a full list see the leaflet inside your medicines packet.
You can report any suspected side effect to the UK safety scheme.
6. How to cope with side effects
What to do about:
- headaches - make sure you rest and drink plenty of fluids. Everyday painkillers, such as paracetamol and ibuprofen, are safe to take with doxycycline.
- feeling or being sick (nausea or vomitting) - stick to simple meals and do not eat rich or spicy food. It might help to take your doxycycline after a meal or snack but avoid dairy products like milk, cheese and yoghurt. Dairy products can stop your body absorbing your medicine properly. If you are being sick, drink plenty of fluids, such as water or squash, to avoid dehydration. Signs of dehydration include peeing less than usual or having strong-smelling pee. Do not take any medicines to treat vomiting without speaking to a pharmacist or doctor.
- sensitivity to sunlight - when you go outside, wear sunglasses and clothes that cover you up. Put sunscreen or sunblock on your skin - with a sun protection factor (SPF) of at least 15 (if you have fair skin, you may need a much higher number than this). Also use a sunscreen product for your lips. Do not use sunlamps or tanning beds. If you get sunburn, there are things you can do to treat your symptoms.
7. Pregnancy and breastfeeding
Doxycycline is not normally recommended in pregnancy or when breastfeeding.
For more information about how doxycycline can affect you and your baby during pregnancy visit the Best Use of Medicines in Pregnancy (BUMPS) website.
Non-urgent advice: Tell your doctor if you're:
- trying to get pregnant
8. Cautions with other medicines
There are some medicines that don't mix well with doxycycline.
Tell your doctor if you're taking these medicines before you start taking doxycycline:
- indigestion remedies (antacids)
- supplements which contain aluminium, bismuth, calcium, magnesium or zinc
- stomach ulcer medicines that contain bismuth
- iron supplements
- other antibiotics
- acne medicines which contain vitamin A, such as isotretinoin
- a blood thinner called warfarin
- medicines for epilepsy, such as phenytoin or carbamazepine
- ciclosporin, a medicine to damp down your immune system
Typhoid vaccine given by mouth may not work properly if you're taking doxycycline. If you need a typhoid vaccine while taking doxycycline, your doctor or nurse will give it by injection.
Mixing doxycycline with herbal remedies and supplements
There are no known problems with taking herbal remedies and supplements with doxycycline.
For safety, tell your doctor or pharmacist if you're taking any other medicines, including herbal remedies, vitamins or supplements.
9. Common questions
How does doxycycline work?
Doxycycline is from a group of medicines called tetracycline antibiotics. These antibiotics kill bacteria by stopping them from making the proteins that they need to survive.
When will I feel better?
For most infections, you should feel better within a few days.
It's very important that you keep taking doxycycline until you finish your medicine. Do this even if you feel better. It will help stop the infection coming back.
What if I don't get better?
If you have rosacea, doxycycline works slowly to treat it. Your doctor will usually review you after 4 to 6 weeks to check how well the medicine is working.
If you are taking doxycycline for any other infection, tell your doctor if you don't start feeling better after 3 days. Also tell them if, at any time, you start to feel worse.
If you are taking doxycycline to prevent malaria, you will not feel any different. You should take doxycycline as prescribed, and continue taking it for 4 weeks after leaving the area where there is malaria.
Will it give me thrush?
Some people get a fungal infection called thrush after taking a course of antibiotics like doxycycline. Antibiotics kill the normal harmless bacteria that help to protect you against thrush.
If this happens to you, ask your pharmacist or doctor for advice.
Will it affect my contraception?
Doxycycline does not affect any type of contraception, including the contraception pill and emergency contraception.
However, if doxycycline makes you vomit or have severe diarrhoea (6 to 8 watery poos in 24 hours) for more than 24 hours, your combined pill may not protect you from pregnancy. Look on the pill packet to find out what to do.
Will it affect my fertility?
There's no firm evidence to suggest that taking doxycycline will reduce fertility in either men or women.
However, speak to a pharmacist or your doctor before taking it if you're trying to get pregnant.
Does it stain teeth?
Doxycycline can build up in growing bones and teeth by binding to calcium. This can stain teeth.
It only happens in growing bones and teeth. This is why doxycycline is not given to children under 12 years old or to pregnant or breastfeeding women.
Can I drive or ride a bike?
Yes, doxycycline shouldn't affect you being able to drive or cycle.
Can I drink alcohol with it?
Avoid drinking alcohol with doxycycline. Alcohol can stop it working properly. Speak to your doctor or pharmacist if you have questions about this.
Is there any food or drink I need to avoid?
Do not take your medicine together with dairy products. This is because dairy foods like milk, cheese and yoghurt can stop your body from absorbing doxycycline. You can have dairy products a few hours before or after your dose.
Avoid drinking alcohol with doxycycline.
I'm allergic to penicillin. Can I take doxycycline?
Yes, you can take doxycycline if you are allergic to penicillin. They are 2 different types of antibiotic.
I'm taking doxycycline to prevent malaria in a hot country, is it better to use another medicine so I don't react to sunlight?
Doxycycline has been used successfully in hot countries for many years. The best way to protect yourself against a reaction to sunlight is to be careful with sun exposure.