From the Guidelines
Doxycycline covers atypical pathogens that Augmentin does not, including Mycoplasma, Chlamydia, Rickettsia, and certain spirochetes like Borrelia (Lyme disease), as well as Human Granulocytic Anaplasmosis (HGA) 1. This is because doxycycline is a tetracycline antibiotic that works by inhibiting bacterial protein synthesis, while Augmentin (amoxicillin/clavulanate) is a beta-lactam/beta-lactamase inhibitor combination that disrupts bacterial cell wall synthesis. Some key points to consider when choosing between doxycycline and Augmentin include:
- Doxycycline is the preferred choice for intracellular pathogens and certain zoonotic infections, such as Lyme disease and HGA 1.
- Augmentin is more effective against many gram-positive organisms and some gram-negative bacteria, particularly those producing beta-lactamases.
- When treating respiratory infections where atypical coverage is needed, doxycycline (100mg twice daily for 5-7 days) may be preferred over Augmentin 1.
- Doxycycline should be avoided in pregnancy and children under 8 years due to effects on bone development and tooth discoloration, while Augmentin is generally safe in these populations 1. It's also worth noting that doxycycline has activity against some protozoan parasites such as malaria, which may be an important consideration in certain cases 1.
From the FDA Drug Label
Doxycycline is indicated for the treatment of the following infections: Rocky Mountain spotted fever, typhus fever and the typhus group, Q fever, rickettsialpox, and tick fevers caused by Rickettsiae. Doxycycline is also indicated for the treatment of infections caused by the following gram-negative microorganisms: Chancroid caused by Haemophilus ducreyi. Doxycycline is indicated for treatment of infections caused by the following gram- negative microorganisms, when bacteriologic testing indicates appropriate susceptibility to the drug: Escherichia coli. 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
Doxycycline covers Rickettsiae, Chlamydia trachomatis, Chlamydia psittaci, Borrelia recurrentis, Haemophilus ducreyi, Yersinia pestis, Francisella tularensis, Vibrio cholerae, Campylobacter fetus, Brucella species, Bartonella bacilliformis, and Calymmatobacterium granulomatis that Augmentin does not.
- Key differences:
- Rickettsial infections: Doxycycline is effective against Rickettsiae, while Augmentin is not.
- Chlamydial infections: Doxycycline is effective against Chlamydia trachomatis and Chlamydia psittaci, while Augmentin is not.
- Borrelia infections: Doxycycline is effective against Borrelia recurrentis, while Augmentin is not.
- Gram-negative microorganisms: Doxycycline has a broader spectrum of activity against gram-negative microorganisms, including Haemophilus ducreyi, Yersinia pestis, and Francisella tularensis. 2
From the Research
Comparison of Doxycycline and Augmentin
- Doxycycline is a semi-synthetic derivative of the tetracycline family, exhibiting bacteriostatic activity against many bacteria, as well as anti-inflammatory activity 3, 4.
- Augmentin, on the other hand, is a combination of amoxicillin and clavulanic acid, and is effective against a wide range of bacterial infections.
- Doxycycline has been shown to be effective against certain infections that Augmentin may not cover, such as:
- Doxycycline also has anti-inflammatory properties, making it suitable for the treatment of non-infectious conditions, such as hair follicle diseases, granulomatous diseases, and vascular proliferation 5.
- In contrast, Augmentin is often used to treat bacterial infections such as pneumonia, skin and soft tissue infections, and urinary tract infections.
- It's worth noting that doxycycline may not be effective against all bacterial infections, and Augmentin may be preferred in certain cases, such as community-acquired meticillin-resistant Staphylococcus aureus (MRSA) skin and soft-tissue infections, where minocycline is often preferred over doxycycline or trimethoprim-sulfamethoxazole 6.