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Tetracyclines are broad-spectrum bacteriostatic antibiotika. It used to be widely used in pediatrics, but only until it was found to damage tooth enamel and growth cartilage .

Antimicrobial spectrum[edit | edit source]

Mechanism of action[edit | edit source]

  • Inhibition of proteosynthesis, reversible binding to the 30S subunit of the ribosome .

Pharmacokinetics[edit | edit source]

  • It is preferred after administration, better on an empty stomach.
  • They form inactive chelates with Ca 2+ , Fe 2+ , Mg 2+ , Al 3+ ions , which limit absorption - do not administer simultaneously with antacids , do not drink with milk.
  • Tissue penetration very good.
  • They penetrate the placenta , high risk of fetal damage.
  • They are widely distributed - in addition to the CNS, they penetrate mainly into bones and teeth , into milk (they cannot be given during pregnancy and lactation).
  • They are concentrated in the liver , subject to enterohepatic circulation, excreted in the bile , and doxycycline is excreted in the faeces, otherwise by the kidneys .

Pharmacodynamics[edit | edit source]

  • Bacteriostaticity does not depend on concentration but on exposure time.
  • Their postantibiotic effect is insignificant.

Side effects[edit | edit source]

  • There are many side effects, which affects the possibility of their use.
  • Bone deposition and interference with tooth enamel , tooth enamel damage, tooth discoloration , phototoxicity, GIT problems ( nausea , vomiting , diarrhea ), suppression of the natural flora in the GIT (may result in blood clotting disorders due to vitamin K deficiency , superinfection), fatty liver degeneration.

Contraindication[edit | edit source]

  • Pregnant and lactating women, children up to 8 years.

Main indications[edit | edit source]

Interaction[edit | edit source]

Representatives[edit | edit source]

1st generation : tetracycline, oxytetracycline, rolitetracycline for im or iv administration.

2nd generation : doxycycline and minocycline.

3rd generation : thiacycline - does not have cross-resistance.

Today, only doxycycline and minocycline are used in practice.

Doxycycline[edit | edit source]

  • Very lipophilic.
  • It is administered parenterally, its absorption is less affected than with other tetracyclines.
  • It has a long half-life (16 hours) - dosing of 12 or 24 hours.
  • Dosage - first day 2 × 100 mg , next days 100 mg every 24 hours.

Minocycline[edit | edit source]

  • Specific indication - acne.

Links[edit | edit source]

Source[edit | edit source]

BENEŠ, Jiří. Studijní materiály [online]. [cit. 2010]. <http://jirben.wz.cz>.

References[edit | edit source]

  • LINCOVÁ, Dagmar a Hassan FARGHALI, et al. Základní a aplikovaná farmakologie. 2. vydání. Praha : Galén, 2007. s. 481-483. ISBN 978-80-7262-373-0.
  • HAVLÍK, Jiří, et al. Infektologie. 2. vydání. Praha : Avicenum, 1990. 393 s. ISBN 80-201-0062-8.
  • LOBOVSKÁ, Alena. Infekční nemoci. 1. vydání. Praha : Karolinum, 2001. 263 s. ISBN 80-246-0116-8.

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Kategorie:Infekční lékařství Kategorie:Farmakologie Kategorie:Mikrobiologie