Dosage
Dose for infections and skin conditions
Your dose of doxycycline depends on why you are taking it. The usual dose is 100mg to 200mg, taken once or twice a day.
You might take a lower dose, such as 40mg once a day or 20mg twice a day, for rosacea or gum infections.
Children younger than 12 years old may need to take a lower dose than adults. The dose depends on your child's age and weight. If you're taking doxycycline more than once a day, try to space your doses evenly throughout the day.
Dose for malaria
You'll usually take 100mg once a day in the morning.
Important
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
If you're taking a lower dose of 40mg of doxycycline a day for rosacea or gum infections, take it at least 1 hour before food.
If you're taking a higher dose of 100mg or more for other types of infection, you can take it with or without food. But 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. Avoid lying down for at least 30 minutes after taking doxycycline.
If you take it twice a day, this could be first thing in the morning, and in the evening – before you go to bed. Try to avoid lying down for at least 30 minutes after taking doxycycline. This helps to prevent any irritation.
If you're taking doxycycline for malaria, start your treatment 1 or 2 days before going to an area with malaria. Stop taking it 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.
How to take capsules or standard tablets
Swallow your doxycycline whole with at least 150ml of water. Not swallowing them with enough water can cause swelling and irritation in your throat (oesophagitis).
How to take dispersible tablets
Dissolve the tablet in a small amount of water. Let the tablet break up fully then swallow the drink.
If you 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. If that happens, just leave out the dose you missed and take your next dose at the usual time.
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 to take your medicines.
If you take too much
Taking 1 extra dose of doxycycline is unlikely to harm you. But speak to your pharmacist or doctor if you're worried, or you have taken more than 1 extra dose.