Doxycycline
Tetracycline antibiotic (Vibramycin). Lyme, malaria prevention, acne, chlamydia, atypical pneumonia. 100 mg standard.
Related comparisons
Amoxicillin vs Ciprofloxacin vs DoxycyclineWHAT IS DOXYCYCLINE?
Detailed overview
Doxycycline is a long-acting tetracycline (Pfizer Vibramycin, FDA 1967). Inhibits bacterial 30S ribosomal subunit (aminoacyl-tRNA binding block). Spectrum: atypicals (Mycoplasma, Chlamydia, Rickettsia, Borrelia, Treponema), some Gram-positive (susceptible Staphylococcus), H. pylori (second-line). Key indications: early-stage Lyme disease, atypical pneumonia, chlamydia STD, malaria prevention (travel), severe acne (low-dose chronic). Side effect profile generally well-tolerated, photosensitivity and GI most common.
ATC code
J01AA02
Prescription
Prescription only (Rx)
Mechanism
30S ribosome-binding protein synthesis inhibitor (tetracycline, bacteriostatic)
Half-life
18-22 h (once or twice daily)
Onset
24-48 h (clinical response)
Data console
Lab data
Safety
Side effects, stop signs, contraindications
Side effects · 8
- Phototoxic reaction: heightened sun sensitivity, severe sunburn-like erythema after brief UV exposure; sun protection and covering clothing are mandatory.
- Esophageal irritation and ulceration: if taken with little water or lying down, the tablet can lodge in the esophagus; take upright with a full glass of water and not immediately before lying down.
- Gastrointestinal upset: nausea, vomiting, diarrhea, loss of appetite, abdominal discomfort; can be reduced by taking with food.
- Candida superinfection: the antibiotic disrupts normal flora, leading to vaginal or oral fungal infection (thrush).
- Intracranial hypertension (pseudotumor cerebri): rare but serious, with headache, visual disturbance and papilledema; risk of permanent vision loss, requires immediate discontinuation.
- Clostridioides difficile-associated diarrhea and pseudomembranous colitis: severe, potentially life-threatening diarrhea can occur during or even after treatment.
- Hepatotoxicity: rare liver function abnormalities, more severe at high doses or in pre-existing liver disease; jaundice or dark urine warrant medical attention.
- Hypersensitivity and skin reactions: rash, urticaria, rarely severe reactions (DRESS, Stevens-Johnson syndrome), and fixed drug eruptions typical of tetracyclines.
Contraindications · 2
- Tetracycline hypersensitivity
- Pregnancy (tooth and bone development damage), child < 8 yr
Related Pharmaceuticals
Same therapeutic category
Studies
Related research and clinical findings
Treatment of Lyme disease: 2020 IDSA guideline
Lantos PM, Rumbaugh J, Bockenstedt LK et al.
Doxycycline for malaria prophylaxis
Tan KR, Magill AJ, Parise ME et al.
Doxycycline in atypical community-acquired pneumonia
Bartlett JG, Mundy LM.
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Educational drug info from official sources (PubMed, FDA, EMA). Does NOT replace medical consultation or the SmPC. Talk to your doctor!
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The information here is for educational and scientific purposes only. Medication use requires medical consultation and a prescription. The indications, dose ranges, and side effects listed here do NOT replace the official Summary of Product Characteristics (SmPC) or consultation with a physician. Do not start or stop any medication on your own. In an emergency, call your local emergency number.