Dr Clare Morrison

Article by Dr Clare Morrison

Doxycycline Side Effects

Doxycycline is an antibiotic that is used to prevent malaria or traveller’s diarrhoea in areas where Mefloquine and Chloroquine are resistant. When it comes to malaria, it is extremely important to take an anti-malarial to prevent or treat malaria, because it can be fatal if no precautions are taken. However, it is important to be aware of the side effects of Doxycycline – which is also used for the treatment of bacterial infections, such as acne, lung, eye, urinary tract, and many more.


The dose regimen to prevent malaria, is usually once daily, to be taken two days before entering a malaria zone, then should be continued once daily during your stay, and for four weeks after returning from a malarious region.

Side effects

Doxycycline is much cheaper than other anti-malarials in the market.  However, it does tend to have slightly more side effects and interactions than the other anti-malarials.

Possible Doxycycline side effects include:

  • Allergic reaction, causing swelling of lips, face or neck, that can lead to difficulty in breathing
  • Skin rash or hives
  • Stomach upset
  • Heartburn
  • Thrush

If any of the above reactions are experienced then the medication should be stopped and a doctor should be consulted immediately. For a full list of Doxycycline side effects see the patient information leaflet.

The most common interactions with taking Doxycycline are:

  • Taking Doxycycline with antacids, milk, calcium, iron, magnesium, and zinc salts. They reduce the absorption of Doxycycline, hence, an interval of at least two hours should be kept when taking this medication.
  • Patients should stay away from direct sunlight while on this Doxycycline as it can cause sun burn.
  • Alcohol interacts with this medication and should not be consumed until the course has been completed. It can affect the amount of time Doxycycline stays in the blood.
  • Doxycycline may affect contraception. Extra precaution should be used, such as condoms or a diaphragm.

This medication SHOULD NOT be taken if the patient:

  • Is under 12 years old, or a pregnant or breastfeeding woman, as it can cause permanent dental staining (yellow-grey-brown) and reduce the growth of bones and teeth of the unborn child.
  • Is taking penicillin antibiotics.
  • Is taking drugs that cause blood clotting, such as warfarin.
  • Suffers from epilepsy and takes medicines like carbamazepine or phenytoin.
  • Has liver problems.
  • Suffers from a disorder where muscles are weak and tire easily.
  • Is likely to be exposed to sunlight or UV light.

Doxycycline is not known to cause drowsiness, and is therefore considered safe when driving or operating machinery.

Dr Clare Morrison
Dr Clare Morrison
Experienced General Practitioner in Hampshire since 1995, with particular interest in Nutrition, Obesity and Smoking Cessation.
Originally published January 06 2014, updated October 06 2018