Page 111 - MNU-PM502- Pharmaeutical Microbiology Theoritical Book

Pharm D- Clinical Pharmacy Program Third Level Pharmaceutical Microbiology& Antimicrobials (PM 502)

Tetracyclines 30s

Tetracycline, doxycycline, and minocycline
Inhibit protein synthesis by act by reversibly binding to the 30S subunit of the

ribosome at the A-site preventing binding of new tRNA molecules loaded with
amino acids.

Spectrum
Broad spectrum
➢ Gram positive bacteria
➢ Gram negative bacteria

➢ Anaerobic bacteria
➢ Atypical bacteria

Toxicity

• Potent chelator of metal ions (calcium) result in the gray to yellow

discoloration of actively forming teeth and deposition in growing bone.

• Should not be given to

➢ pregnant and lactating women (teratogenic)
➢ children < 8 years

• Photosensitivity

• Hepatic and renal toxicity

• GIT distress

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