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Generic Name: Doxycycline 

Brands: Vibramycin, Oracea, Adoxa, Atridox, Acticlate, Acticlate Cap, Doryx, Doxyhexal, Doxylin, Monodox

Class: Antibiotics

Availability: Prescription only

Molecular Formula: C24H33ClN2O10

Substance UNII: 334895S862

What is Doxycycline?

Doxycycline is a tetracycline (containing 4 hydrocarbon rings) antibiotic. It is often sold under the brand names Vibramycin, Oracea, Adoxa, Atridox, Acticlate, Acticlate Cap, Doryx, Doxyhexal, Doxylin, and Monodox.

What is Doxycycline Used For?

According to the U.S. National Library of Medicines, doxycycline is indicated for (recommended for) the treatment of infections such as:

  • Rocky Mountain spotted fever, typhus fever and the typhus group, Q fever, rickettsialpox, and tick fevers caused by Rickettsiae
  • Respiratory tract infections caused by Mycoplasma pneumoniae
  • Lymphogranuloma venereum caused by Chlamydia trachomatis
  • Psittacosis (ornithosis or parrot fever) caused by Chlamydophila psittaci
  • Trachoma caused by Chlamydia trachomatis
  • Inclusion conjunctivitis or chlamydial conjunctivitis (pink eye) caused by Chlamydia trachomatis
  • Uncomplicated urethral, endocervical, or rectal infections in adults caused by Chlamydia trachomatis
  • Nongonococcal urethritis (inflammation of the urethra) caused by Ureaplasma urealyticum
  • Relapsing fever due to Borrelia recurrentis
  • Acne or other infections not in this list

Doxycycline is also indicated for the treatment of infections caused by the following gram-negative microorganisms:

  • Chancroid (an STI) caused by Haemophilus ducreyi
  • Plague due to Yersinia pestis
  • Tularemia (rabbit fever or deer fly fever) due to Francisella tularensis
  • Cholera caused by Vibrio cholerae
  • Campylobacter fetus infections caused by Campylobacter fetus
  • Brucellosis (Mediterranean fever) due to Brucella species (in conjunction with streptomycin)
  • Bartonellosis due to Bartonella bacilliformis
  • Granuloma inguinale (aka donovanosis, a rare STI in the US) caused by Klebsiella granulomatis

Doxycycline is indicated for treatment of infections caused by the following gram-negative bacteria, when bacteriologic testing indicates appropriate susceptibility to the drug:

  • Escherichia coli
  • Enterobacter aerogenes
  • Shigella species
  • Acinetobacter species
  • Respiratory tract infections caused by Haemophilus influenzae
  • Respiratory tract and urinary tract infections caused by Klebsiella species

Doxycycline is indicated for treatment of infections caused by the following gram-positive microorganisms when bacteriologic testing indicates appropriate susceptibility to the drug:

  • Upper respiratory infections caused by Streptococcus pneumoniae
  • Anthrax due to Bacillus anthracis, including inhalational anthrax (post-exposure)

When penicillin is contraindicated, doxycycline is an alternative drug in the treatment of the following infections:

  • Uncomplicated gonorrhea caused by Neisseria gonorrhoeae
  • Syphilis caused by Treponema pallidum
  • Yaws caused by Treponema pallidum, subspecies pertenue
  • Listeriosis due to Listeria monocytogenes
  • Vincent infection (Vincent gingivitis, trench mouth, Vincent stomatitis, Vincent angina, acute necrotizing ulcerative gingivitis) caused by Fusobacterium fusiforme
  • Actinomycosis caused by Actinomyces israelii
  • Infections caused by Clostridium species

Moreover, in acute intestinal amebiasis (amebic dysentery), doxycycline may be a useful adjunct to amebicides. In some cases, doxycycline may be useful adjunctive therapy in severe acne.

Doxycycline is also indicated for the prophylaxis (prevention) of malaria due to Plasmodium falciparum in short-term travelers (<4 months) to areas with chloroquine and/or pyrimethamine-sulfadoxine resistant strains. Also, used for Acne or other infections not in the list above.

How Does Doxycycline Work?

Doxycycline kills the bacteria by inhibiting bacterial protein synthesis. In other words, it stops the bacteria by preventing them from replicating.

How Long Does it Take for Doxycycline to Work?

When taking doxycycline to treat infections, you should start feeling better after a few days. However, it is important to complete the prescribed cycle for the antibiotic to be effective. Consult your doctor if you don’t notice any improvement or your symptoms worsen within 3 days of starting the therapy.

Do Not Use Doxycycline If:

There are several situations where this medication may not be the right choice for you. According to the U.K National Health Service (NHS), the following should not use doxycycline:

  • People who have had an allergic reaction to doxycycline or any other medicine in the past
  • Patients with kidney or liver problems.
  • Patients with an inflamed food pipe (esophagitis).
  • People with lupus, an autoimmune disease
  • Those who suffer from myasthenia gravis (MG), an illness that causes severe muscle wasting
  • Pregnant and nursing individuals

Please note that this list may not be complete, and there may be other situations where doxycycline use is not advisable.

Disclaimer: this article does not constitute or replace medical advice. If you have an emergency or a serious medical question, please contact a medical professional or call 911 immediately. To see our full medical disclaimer, visit our Terms of Use page.


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