From the Guidelines
Doxycycline is a tetracycline-class antibiotic. It belongs to the broader tetracycline family of antibiotics, which work by inhibiting bacterial protein synthesis by binding to the 30S ribosomal subunit, preventing the attachment of aminoacyl-tRNA to the mRNA-ribosome complex. This mechanism makes doxycycline bacteriostatic, meaning it prevents bacteria from multiplying rather than directly killing them. Doxycycline is effective against a wide range of gram-positive and gram-negative bacteria, as well as some atypical organisms like Chlamydia, Mycoplasma, and Rickettsia. It's commonly used to treat respiratory infections, skin infections, urinary tract infections, certain sexually transmitted infections, malaria prophylaxis, and acne. Doxycycline has good tissue penetration and a relatively long half-life, allowing for once or twice daily dosing. Some key points to consider when using doxycycline include:
- It can cause permanent tooth discoloration in children under 8 years old and should be avoided during pregnancy due to potential effects on fetal bone development 1.
- Doxycycline may cause photosensitivity, which is a concern, because early Lyme disease occurs most commonly during the summer months, and individuals treated with doxycycline are advised to avoid exposure to the sun while receiving therapy 1.
- The use of oral tetracycline-class antibiotics like doxycycline has been associated with inflammatory bowel disease (IBD), pharyngitis, Clostridium difficile infection, and Candida vulvovaginitis 1.
- Outpatient antibiotic stewardship promotes appropriate antibiotic use in which patients receive the right dose of the antibiotic at the right time for the right duration, and doxycycline is no exception to this principle 1.
From the FDA Drug Label
Doxycycline is a broad-spectrum antibiotic synthetically derived from oxytetracycline,
- Doxycycline is classified as a broad-spectrum antibiotic and is specifically a tetracycline antibiotic 2
From the Research
Classification of Doxycycline
- Doxycycline is a semi-synthetic structural isomer of the tetracycline family 3, 4.
- It is also referred to as a synthetic tetracycline 5.
- Tetracyclines, including doxycycline, are a class of broad-spectrum antibiotics 6, 7.
Properties and Uses
- Doxycycline exhibits good intra-cellular penetration, with bacteriostatic activity on many bacteria 3.
- It has anti-inflammatory properties, making it suitable for the treatment of noninfectious conditions 5.
- Doxycycline is used to treat various diseases, including acne, rosacea, chlamydial and mycoplasma urethritis, and other infectious diseases 3, 5, 4.
- It is also used as a preventive measure for malaria 4.
Pharmacokinetics and Safety
- Doxycycline is rapidly and almost completely absorbed by the digestive tract, with food having no incidence on absorption 3.
- It has a high but labile affinity for proteins and rapidly diffuses in the extravascular compartment and most tissues 3.
- The main excretion route is through bile, with slower excretion by the kidney 3.
- Doxycycline is generally well tolerated, with common adverse effects including stomach upset, nausea, and diarrhea 4.