Doxycycline: Indications, How to Take, Doses & Side Effects

Updated in December 2023

Doxycycline is an tetracycline antibiotics that works by blocking bacterial metabolism to stop bacterial growth, This antibiotic can be used to treat diseases like typhoid fever, pneumonia, urinary tract infections, syphilis, gonorrhea or chlamydia. It can also be used to prevent conditions like malaria, cholera and leptospirosis. 

This medication is available for purchase at pharmacies with a doctor’s prescription.  

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Indications for use

Doxycycline is indicated for the treatment of bacterial infections like: 

  • Urinary tract infections 
  • Kidney infections
  • Pneumonia
  • Gonorrhea
  • Chlamydia
  • Syphilis
  • Rickettsiosis
  • Louse-borne relapsing fever
  • Tick fever
  • Typhoid fever
  • Lymphogranuloma venereum 
  • Uterine infections, like endocervicitis 
  • Bacterial pink eye
  • Testicular inflammation
  • Inguinal granuloma
  • Lyme disease 
  • Parrot fever
  • Psitacose
  • Brucellosis

Doxycycline can be used to treat severe acne, swelling and acne-like lesions caused by rosacea. It can be used to treat leptospirosis, cholera and malaria, even though these conditions are not caused by bacteria. The infectious agent responsible for these conditions is sensitive to doxycycline however. 

How to take and dosing

Doxycycline is taken orally as a pill with a cup of water on an empty stomach. It should be taken 1 to 2 hours before a meal. 

If you forget to take a dose, you should take doxycycline as soon as you remember, and then readjust the hours for your next doses according to the doctor’s instructions. You should never double a dose to make up for a forgotten one. 

The recommended dose varies depending on the patient’s age: 

  • Adults: The recommended dose is two 100 mg pills as a single dose, or one 100 mg pill every 12 hours on the first day of treatment, After the second day, take one 100 mg pill as a single dose per day. The doctor can also prescribe doses of 200 mg  as necessary. 
  • Children over 8 years weighing less than 45 kg:  Therecommended dose is 2.5 to 5 mg per kilogram of weight per day, administered as a single dose or divided into two daily doses.  
  • Children over 8 years weighing over 45 kg: The daily recommended dose is the same as adults. 

The duration of treatment depends on the type of infection the patient is presenting with, and will be established by the doctor. 

Side effects

Some of the most common side effects of doxycycline include stomach ache, diarrhea, nausea, indigestion, light sensitivity, lack of appetite, blurry vision, tooth discoloration, ringing ears or headaches. 

Contraindications for use

Doxycycline should not be used by pregnant or breastfeeding women, children less than 8, or patients with an allergy to tetracyclines.