Doxycycline at a glance
Medicine class
Tetracycline antibiotic.
Main roles
Treats selected respiratory, urinary, sexually transmitted and skin infections; also licensed for malaria prevention.
Taking capsules
Swallow with plenty of water while sitting or standing, and do not lie down immediately afterwards.
Sun sensitivity
May make skin unusually sensitive to sunlight and ultraviolet light.
What is Doxycycline used for?
This capsule is licensed for susceptible infections and certain preventive uses. Choice should reflect the organism, clinical circumstances and current antimicrobial or travel-health guidance.
Respiratory infections, including some pneumonias, lower respiratory infections, chronic bronchitis and sinusitis.
Susceptible urinary tract infections.
Chlamydial and other specified sexually transmitted infections; an alternative in selected cases of gonorrhoea or syphilis.
Acne when antibiotic treatment is considered necessary.
Certain eye, rickettsial, tick-borne and other uncommon infections.
Treatment of chloroquine-resistant falciparum malaria alongside an appropriate rapid-acting antimalarial.
Prevention of malaria and specified risks including scrub typhus, leptospirosis and enterotoxigenic E. coli travellers’ diarrhoea.
How does Doxycycline work?
Doxycycline mainly stops susceptible microorganisms multiplying by blocking microbial protein production.
Doxycycline preparations and strengths
Capsule
Route: Oral
Strengths: 50 mg, 100 mg
How to take Doxycycline
Take doxycycline exactly as shown on the dispensing label. Instructions can vary between formulations.
Swallow the capsule whole with plenty of water while sitting or standing.
Take it well before bed and remain upright for at least 30 minutes to reduce throat and oesophageal irritation.
If it irritates your stomach, this capsule may be taken with food or milk.
Keep taking it as prescribed unless a healthcare professional tells you to stop.
Separate it as far as possible from antacids and products containing iron, zinc, bismuth, aluminium, calcium or magnesium.
Doxycycline side effects
Common or expected effects
- Headache.
- Nausea or vomiting.
- Rash.
- Increased sensitivity to sunlight or ultraviolet light.
Get urgent medical advice
- Severe allergic reaction, including breathing difficulty or facial, tongue or throat swelling.
- Severe, blistering, peeling or widespread skin reaction.
- Bloody diarrhoea or severe abdominal pain, which may indicate antibiotic-associated bowel inflammation.
- Severe headache with vomiting or visual disturbance, which may indicate raised pressure around the brain.
- Oesophageal inflammation or ulceration, with painful swallowing or chest pain.
- Symptoms of significant liver or blood-cell problems, such as jaundice, unusual bruising or recurrent infections.
Doxycycline in pregnancy
This capsule’s product information contraindicates doxycycline during pregnancy because of concerns about developing teeth and bone. Early exposure is not known to harm the baby, and a tetracycline may occasionally be considered when it is the only suitable treatment for a serious infection. Contact the prescriber if pregnant, planning pregnancy or pregnancy occurs during treatment; do not stop essential treatment without advice.
Doxycycline while breastfeeding
This capsule’s product information contraindicates use during breastfeeding. UK specialist guidance states that doxycycline can sometimes be used cautiously after individual assessment, particularly for short-term treatment while breastfeeding a full-term, healthy infant. Monitor the infant for rash, vomiting, diarrhoea, oral thrush or nappy rash and seek professional advice if these occur.
Doxycycline interactions
Tell the prescriber or pharmacist about all medicines, supplements and non-prescription products. Important examples include:
Antacids; iron, zinc, bismuth, calcium, magnesium or aluminium products
Can reduce doxycycline absorption; separate administration as far as possible.
Warfarin and related anticoagulants
The anticoagulant effect may increase, requiring closer coagulation monitoring and possible treatment adjustment.
Carbamazepine, phenytoin and barbiturates
May shorten doxycycline exposure and reduce its effect.
Common questions about Doxycycline
Answers are fully visible for fast scanning and source review.
Can doxycycline hyclate capsules be taken with food or milk?
Yes. For this capsule, food or milk may be used if stomach irritation occurs, and absorption is not notably affected.
Why must I stay upright after taking doxycycline?
Capsules can lodge in and irritate the oesophagus. Plenty of water and remaining upright reduce the risk of inflammation or ulceration.
Sources
These sources were used to prepare and review this medicine page.
Prepared and reviewed by the iatroX editorial team.