ANTI INFECTIVES pt2

• Anti-infectives in dentistry

  • Penicillins
  • Erythromycin
  • Clindamycin
  • Tetracyclines
  • Cephalosporins
  • Metronidazole
• First generation penicillins

  • Pen G
  • Pen V
  • Penicillinase resistant penicillins
• Penicillins

  Bactericidal potency, lack of toxicity, and of spectrum of action
• Penicillins

  Very potent bactericidal agent that acts by interfering with synthesis of bacterial cell wall
• Penicillins

  Administered orally, parenterally but not topically
• Penicillins

  Drug of choice for prophylaxis in non-allergic patients with a history of RHD
• Penicillins

  Effective against oropharyngeal strains of Bacteriodes
• Adverse reactions to penicillins

  • Hypersensitivity reactions
  • Anaphylactic reaction
  • Serum reaction
  • Drug fever
  • Rashes
• Oral penicillin adverse reactions

  • Tongue inflammation
  • Nausea and vomiting
  • Diarrhea
• Extended spectrum penicillin

  Pseudomembranous colitis - diarrhea caused by a change in the flora of the colon or an overgrowth of a toxin producing strain of Clostridium difficile
• Oxacillin


  Cause liver toxicity
• Penicillin V

  Use exclusively in dental situations when an oral narrow spectrum antibiotic is indicated
• Penicillin G


  Prototype penicillin, poorly absorbed orally (must be given in large doses), used on once daily basis
• Sodium and Potassium Pen G


  Parenteral and oral, detrimental to patients with cv disease on low sodium diet
• Procaine Pen G


  Used in combination with oral PROBENECID as a single dose injection for the treatment of certain sexually transmitted disease
• Benzathine Pen G


  IM to provide an extended duration of action, for patients with a history of rheumatic heart disease and undergoing long term prophylaxis of bacterial endocarditis
• Penicillinase-resistant penicillin


  Use against penicillinase resistant staphylococci, patients allergic to penicillin are also allergic, stable enough to be administered orally (Cloxacillin and dicloxacillin)
• Extended-spectrum penicillins

  • Ampicillin-like agents
  • Carbenicillin-like agents
  • Amidinopenicillin
• Ampicillin-like agents


  Active against E.coli, H. Influenza, Salmonella, Shigella, decreased absorption when administered with food, parenteral ampicillin + GENTAMYCIN (for high risk cardiac patients)
• Carbenicillin-like agents


  Reserved for hospitalized patients with serious infections caused by Pseudomonas and E. Coli strains, combined with gentomycin or tobramycin, carbenicillin indanyl used orally for urinary tract infection
• Erythromycin


  Macrolide, inhibits RNA, a good alternative to penicillin, drug of choice for whooping cough, diptheria, atypical pneumonia, Legionnaires' disease, chlamydia infection, syphilis and gonorrhea, food reduces absorption, for prophylaxis of patients with RHD (Rheumatic Heart Disease)
• Adverse reactions to erythromycin

  • Epigastric distress
  • Cholestatic jaundice
  • Ototoxicity
• Erythromycin drug interactions

  Reduce the rate of elimination of Theophylline (high dose) chronic asthma, implicated in the failure of oral contraceptives
• Clindamycin


  Bacteriostatic antibiotic effective against gram positive organism, effective against anaerobic microorganism Bacteriodes and some staphylococcal infections, use when patient is allergic to penicillin
• Clindamycin adverse reactions

  • Glossitis
  • Stomatitis
  • Pseudomembranous colitis
  • Superinfection
• Tetracyclines

  • Tetracycline
  • Terramycin
  • Doxycycline
  • Minocycline (Minocin)
  • can cause osteomyelitis
• Tetracyclines


  Broad spectrum antibiotic affecting a wide range of microorganism, bacteriostatic, interferes with synthesis of bacterial protein by binding at the 30S subunit of bacterial ribosome, wide tissue distribution, secreted in the saliva and the milk of lactating mothers
• Tetracyclines

  All tetracyclines cross the placental barrier and binds to tissues undergoing calcification, if used during the period of enamel calcification, it can produce permanent discoloration of the teeth and enamel hypoplasia, should not be used during the last half of pregnancy or to an infant (4-6 months) - primary teeth will be affected, if administered to infants between 2 months to 8 years old, permanent teeth will be affected, may also cause temporary stunting of growth
• Tetracycline pharmacokinetics

  Dairy food in the diet decreases the absorption of tetracyclines except with Doxycycline, all tetracycline enter the cerebrospinal fluid but insufficient to be therapeutic except for Minocycline, all tetracyclines are metabolized in the liver, tetracycline is eliminated by glomerular filtration, Minocycline excreted in the urine, Doxycycline excreted in the feces, Doxycycline for treating infections in renally compromised patients
• Tetracycline uses

  Use for the treatment of Chlamydial infections, Ricketts, Mycoplasma Pneumonia, Cholera, in low dosages effectively treat acne because they can decrease fatty acid content of sebum, used for localized juvenile periodontitis
• Adverse reactions to tetracyclines

  • Gastrointestinal effects: anorexia, nausea, vomiting, diarrhea, xerostomia, superinfection (moniliasis)
  • Implicated in the failure of oral contraceptives
  • Photosensitivity reactions (red rash on areas exposed to sunlight)
• Cephalosporins

  Chemically related to penicillin, inhibits cell wall synthesis, bactericidal agents that are active against gram (+) (-) organism, Cephalexin, Cephradine are needed to treat dental infection, for prophylaxis before dental procedure to prevent bacterial endocarditis BUT not a substitute to penicillin or erythromycin, inhibits Salmonella, Klebsiella, administered parenterally because they aren't absorbed from the GI tract, can produced localized pain, induration and swelling (IM) and abscess and thrombophlebitis (IV)
• Adverse reactions to cephalosporins

  • Confusion
  • Seizures
  • Nausea
  • Vomiting
  • Diarrhea
  • Renal impairment, liver disease - decrease prothrombin activity leading to increased bleeding
  • Hypersensitivity: hives, itching, measles type rash, serum sickness - edema, fever, hives and inflammation
• Metronidazole


  Bactericidal, penetrates all bacterial cells, medical use is to inhibit amoebiasis, trichomoniasis, effectiveness in treating dry socket, improvement in periodontal patients