What it is used for
- Chest and respiratory infections
- Acne and rosacea
- Some sexually transmitted infections such as chlamydia
- Certain tick-borne illnesses such as Lyme disease
- Prevention and treatment of some types of malaria
- Some skin and dental infections
How it works
Doxycycline is a tetracycline antibiotic. It stops bacteria from making the proteins they need to grow, which prevents them from multiplying. It is also used to reduce inflammation in conditions such as acne and rosacea.
How it is taken
Comes as capsules and tablets, and sometimes an injection in hospital. Take it exactly as your doctor or pharmacist directs and follow the label. Take it with a full glass of water and stay upright (sitting or standing) for a while afterwards to protect the food pipe. Taking it with food can reduce stomach upset.
No doses here on purpose. The right strength and schedule depend on you — only a doctor or pharmacist should set them. Always follow your prescription and the label.
Common side effects
- Nausea
- Stomach upset
- Diarrhoea
- Increased sensitivity to sunlight (sunburn more easily)
- Thrush
- Loss of appetite
Serious effects — get help
- Severe allergic reaction with swelling or breathing difficulty
- Pain or difficulty swallowing or chest pain (possible irritation or ulcer of the food pipe)
- Severe headache with blurred vision (rare pressure around the brain)
- Severe, persistent or bloody diarrhoea
- Severe blistering skin reactions
- Yellowing of the skin or eyes
If a reaction is severe — for example trouble breathing, swelling of the face or throat, or collapse — go to the nearest emergency room now or call your local emergency number. Do not wait for an online consultation.
Interactions to watch
- Antacids and supplements containing calcium, iron, magnesium or zinc (separate the timing)
- Dairy products
- Blood thinners such as warfarin
- Some epilepsy medicines
- Oral retinoid acne medicines (avoid combining)
- Penicillin-type antibiotics
Who should take care
- Not usually given in pregnancy, breastfeeding or to young children as it can affect developing teeth and bones
- Tell your clinician if you have liver problems
- Use sun protection because skin can burn more easily
- Take with water and stay upright to protect the food pipe
- Mention any other medicines and supplements you take