Tetracycline

Mechanism-of-action class: Protein Synthesis Inhibitors.

• To reduce the development of drug-resistant bacteria and maintain the effectiveness of tetracycline hydrochloride and other antibacterial drugs, tetracycline hydrochloride should be used only to treat infections that are proven or strongly suspected to be caused by susceptible bacteria. When culture and susceptibility information are available, they should be considered in selecting or modifying antibacterial therapy.

• This drug is contraindicated in persons who have shown hypersensitivity to any of the tetracyclines.contraindicated

Adults Usual daily dose, 1 gram as 500 mg twice a day or 250 mg four times a day. Higher doses such as 500 mg four times a day may be required for severe infections or for those infections which do not respond to the smaller doses. For pediatric patients above eight years of age Usual daily dose, 10 mg/lb to 20 mg/lb (25mg/kg to 50 mg/kg) body weight divided in four equal doses. Administration of adequate amounts of fluid with the capsule formulation of tetracycline is recommended to wash down the drug and reduce the risk of esophageal irritation and ulceration (see ADVERSE REACTIONS ). Absorption of tetracycline is impaired by antacids containing aluminum, calcium or magnesium and preparations containing iron, zinc or sodium bicarbonate. Food and some dairy products also interfere with absorption. When used in streptococcal infections, therapy should be continued for 10 days. For treatment of brucellosis, 500 mg tetracycline four times a day for three weeks accompanied by streptomycin, 1 gram intramuscularly twice daily the first week and once daily the second week. For the treatment of syphilis in patients allergic to penicillin, the following dosage of tetracycline is recommended: early syphilis (less than one year's duration), 500 mg four times a day for 15 days. Syphilis of more than one year's duration (except neurosyphilis), 500 mg four times a day for 30 days. For treatment of gonorrhea, the recommended dose is 500 mg by mouth four times a day for seven days.

Tooth Development The use of drugs of the tetracycline-class during tooth development (last half of pregnancy, infancy and childhood to the age of 8 years) may cause permanent discoloration of the teeth (yellow-gray-brown). This adverse reaction is more common during long-term use of the drugs but it has been observed following repeated short-term courses. Enamel hypoplasia has also been reported. Tetracycline drugs should not be used in this age group, except for anthrax, unless other drugs are not likely to be effective or are contraindicated. Clostridium difficile Associated Diarrhea Clostridium difficile associated diarrhea (CDAD) has been reported with use of nearly all antibacterial agents, including tetracyclines, and may range in severity from mild diarrhea to fatal colitis. Treatment with antibacterial agents alters the normal flora of the colon leading to overgrowth of C . difficile. C. difficile produces toxins A and B which contribute to the development of CDAD. Hypertoxin producing strains of C. difficile cause increased morbidity and mortality, as these infections can be refractory to antimicrobial therapy and may require colectomy. CDAD must be considered in all patients who present with diarrhea following antibacterial drugs. Careful medical history is necessary since CDAD has been reported to occur over two months after the administration of antibacterial agents. If CDAD is suspected or confirmed, ongoing use of antibacterial drugs not directed against C. difficile need to be discontinued.

Gastrointestinal: anorexia, nausea, epigastric distress, vomiting, diarrhea, glossitis, black hairy tongue, dysphagia, enterocolitis, and inflammatory lesions (with Candida overgrowth) in the anogenital region. Esophagitis and esophageal ulceration have been reported in patients receiving particularly the capsule and also the tablet forms of tetracyclines. Most of the patients were reported to have taken medication immediately before going to bed (see DOSAGE AND ADMINISTRATION ). Teeth : permanent discoloration of teeth may be caused during tooth development. Enamel hypoplasia has been reported (see WARNINGS ). Skin : fixed drug eruption, maculopapular and erythematous rashes. Exfoliative dermatitis has been reported. Onycholysis and discoloration of the nails have been reported. Photosensitivity is discussed in WARNINGS . Renal Toxicity : an increase in BUN has been reported and is dose related. Liver : hepatotoxicity and liver failure have been observed in patients receiving tetracycline and in tetracycline-treated patients with renal impairment. Hypersensitivity Reactions : urticaria, angioneurotic edema, anaphylaxis, anaphylactoid purpura, pericarditis, exacerbation of systemic lupus erythematosus, and serum sickness-like reactions, as fever, rash, and arthralgia. Blood : hemolytic anemia, thrombocytopenia, thrombocytopenic purpura, neutropenia and eosinophilia have been reported. When given over prolonged periods, tetracyclines have been reported to produce brown-black microscopic discoloration of thyroid glands.

Pregnancy Teratogenic Effects Pregnancy Category D (see WARNINGS ) Nonteratogenic Effects (see WARNINGS ) Pregnant women with renal disease may be more prone to develop tetracycline-associated liver failure.

In case of overdosage, discontinue medication, treat symptomatically and institute supportive measures. Tetracycline is not dialyzable.

• Oct 8, 1957NDANDA050278Avet
• Feb 10, 1971ANDAANDA061147Strides Pharma Intl
• Dec 24, 1974ANDAANDA061837Watson Labs
• Aug 12, 1988ANDAANDA062752Chartwell Tetra
• Sep 28, 2006NDANDA050786Labs Juvise
• Sep 18, 2018ANDAANDA210674Amneal Pharms Ny
• Nov 7, 2018ANDAANDA210662Breckenridge
• Mar 6, 2023ANDAANDA205770Ph Health

1. 1Off Label Use28515%
2. 2Nausea20311%
3. 3Diarrhoea1659.0%
4. 4Drug Hypersensitivity1628.8%
5. 5Vomiting1618.7%
6. 6Headache1578.5%
7. 7Dizziness1447.8%
8. 8Hypersensitivity1387.5%
9. 9Asthenia1286.9%
10. 10Arthralgia1196.5%
11. 11Fatigue1196.5%
12. 12Pain In Extremity1166.3%
13. 13Drug Ineffective1136.1%
14. 14Muscular Weakness1106.0%
15. 15Urticaria1095.9%

Recent PubMed references pinned to Tetracycline as a MeSH major topic. Citations link to pubmed.ncbi.nlm.nih.gov.

• Ratiometric Fluorescence and Smartphone-Assisted Visual Assay of Tetracycline and Levofloxacin Based on Dual-Emission Carbon Dots.
  Luminescence : the journal of biological and chemical luminescence · 2026 · Guo B, Wu M, Wang D, et al.
  PMID 42270436DOI 10.1002/bio.70538
• A self-powered photoelectrochemical sensor based on an In(2)O(3)/Ag(2)S heterojunction for tetracycline detection and portable applications.
  Mikrochimica acta · 2026 · Li J, Li H, Hao Y, et al.
  PMID 42249178DOI 10.1007/s00604-026-08170-9
• Synergistic enhancement mechanism of biochar from Chinese medicine residue for tetracycline hydrochloride removal.
  Journal of environmental management · 2026 · Xu E, Song X, Liu Y, et al.
  PMID 42190530DOI 10.1016/j.jenvman.2026.129992
• Mediator-assisted tetracycline transformation and dye decolorization by a thermostable recombinant laccase from Yersinia enterocolitica.
  Enzyme and microbial technology · 2026 · Özdemir Fİ, Şükür G, Yiğit BM, et al.
  PMID 42176614DOI 10.1016/j.enzmictec.2026.110903
• Defect regulation of Co-loaded three-dimensional graphene for degradation of tetracycline in a tetracycline/Cu(2+) coexistence matrix via peroxymonosulfate activation.
  Environmental research · 2026 · Wang X, Duan J, Zhou G, et al.
  PMID 42167515DOI 10.1016/j.envres.2026.124812
• Enhanced tetracycline elimination by template-synthesized mesoporous biochar: Adsorption performance and mechanistic insights.
  Journal of environmental management · 2026 · Li P, Guo D, Meng L, et al.
  PMID 42167164DOI 10.1016/j.jenvman.2026.129978
• Directional charge transfer driven by superior interfacial electric field in AT-PDI/BOB toward simultaneous removal of tetracycline and Cr(VI).
  Environmental research · 2026 · Jie Z, Jiang W, Zhang X, et al.
  PMID 42162718DOI 10.1016/j.envres.2026.124798
• γ-Fe(2)O(3)/choline-tagged nanocellulose (ChNC) as a new bio-nanocomposite for tetracycline adsorptive removal and catalytic novel synthesis of pyrazolo-quinolinones.
  International journal of biological macromolecules · 2026 · Tamaddon F, Ahmadi-AhmadAbadi E
  PMID 42155751DOI 10.1016/j.ijbiomac.2026.152599

The 10 most recently updated of 817 ClinicalTrials.gov registrations naming Tetracycline as an intervention. Registration is not evidence of efficacy or safety — reference crosswalk only.

• Tetracycline Treatment Tolerability Trial
  Completed · Phase 2 · Interventional · 60 enrolled · Johns Hopkins University
  NCT05219929updated 2026-06-11
• Doxycycline Host-directed Therapy to Improve Lung Function and Decrease Tissue Destruction in Pulmonary Tuberculosis
  Recruiting · Phase 3 · Interventional · 150 enrolled · National University Hospital, Singapore
  NCT05473520updated 2026-06-09
• Effects of Treatments on Atopic Dermatitis
  Recruiting · Phase 2 · Interventional · 130 enrolled · National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS)
  NCT01631617updated 2026-06-09
• Analysis of the Microbiome in Rosacea
  Active not recruiting · Early phase 1 · Interventional · 150 enrolled · Johns Hopkins University
  NCT04108897updated 2026-06-08
• Clinical and Radiographic Evaluation of Doxycycline and Atorvastatin Loaded Chitosan Nanoparticles as an Adjunctive to Scaling and Root Planning in the Management of Chronic Periodontitis. A Randomized Controlled Clinical Trial.
  Not yet recruiting · Phase 4 · Interventional · 80 enrolled · Fayoum University
  NCT07634341updated 2026-06-08
• Isotretinoin vs. Doxycycline for Acneiform Rash in Patients Receiving Drugs That Target the MAPK Pathway
  Not yet recruiting · Phase 2 · Interventional · 50 enrolled · University of California, San Francisco
  NCT07629167updated 2026-06-05
• Enhanced Dermatological Care to Reduce Rash and Paronychia in Epidermal Growth Factor Receptor (EGRF)-Mutated Non-Small Cell Lung Cancer (NSCLC) Treated First-line With Amivantamab Plus Lazertinib
  Active not recruiting · Phase 2 · Interventional · 305 enrolled · Janssen Research & Development, LLC
  NCT06120140updated 2026-06-05
• Comparative Effectiveness Study of Spironolactone Versus Doxycycline for Acne
  Active not recruiting · Phase 4 · Interventional · 350 enrolled · University of Pennsylvania
  NCT04582383updated 2026-06-05
• A Pilot of Pediatric/Adult Study of Gene Expression Profiling and Clinical Characterization of Phototoxicity
  Completed · Phase 1 · Interventional · 62 enrolled · National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS)
  NCT00353158updated 2026-06-05
• Sanitation, Water, and Instruction in Face-washing for Trachoma I/II
  Completed · Phase 3 · Interventional · 47,605 enrolled · University of California, San Francisco
  NCT02754583updated 2026-06-04

Frequently asked questions

How does Tetracycline work?

Mechanism-of-action class: Protein Synthesis Inhibitors.

What is Tetracycline used for?

According to FDA labeling, Tetracycline carries indications including: To reduce the development of drug-resistant bacteria and maintain the effectiveness of tetracycline hydrochloride and other antibacterial drugs, tetracycline hydrochloride should be used only to treat infections that are proven or strongly suspected to be caused by susceptible bacteria. When culture and susceptibility information are available, they should be considered in selecting or modifying antibacterial therapy.. This is a reference summary of labeled uses, not medical advice or a treatment recommendation.

What class of drug is Tetracycline?

Tetracycline is classified as Antibiotics, Antiinfectives, Antiinfectives and antiseptics for local oral treatment, Tetracycline and derivatives, Tetracyclines, Tetracycline-class Antimicrobial, Protein Synthesis Inhibitors, Cell Membrane Alteration, Decreased Mitosis, Decreased Protein Synthesis.

What are the brand names for Tetracycline?

Tetracycline is marketed under brand names including Pylera, Viabecline, Vitastem.

What are the contraindications for Tetracycline?

Tetracycline labeling lists contraindications including: This drug is contraindicated in persons who have shown hypersensitivity to any of the tetracyclines.. Always consult the full prescribing information and a clinician.