Flucloxacillin, Uses, Dosage, Side Effects, Interactions, Pregnancy

Flucloxacillin
Flucloxacillin is a narrow-spectrum, semisynthetic isoxazolyl penicillin with antibacterial activity. Floxacillin binds to and inactivates penicillin-binding proteins (PBPs) located on the inner membrane of the bacterial cell wall. Inactivation of PBPs interferes with the cross-linkage of peptidoglycan chains necessary for bacterial cell wall strength and rigidity. This interrupts bacterial cell wall synthesis and results in the weakening of the bacterial cell wall, eventually causing cell lysis.
Flucloxacillin is only found in individuals that have used or taken this drug. It is an antibiotic analog of cloxacillin. By binding to specific penicillin-binding proteins (PBPs) located inside the bacterial cell wall, flucloxacillin inhibits the third and last stage of bacterial cell wall synthesis. Cell lysis is then mediated by bacterial cell wall autolytic enzymes such as autolysins; it is possible that flucloxacillin interferes with an autolysin inhibitor.
Flucloxacillin (INN) or floxacillin is a narrow-spectrum beta-lactam antibiotic of the penicillin class. It is used to treat infections caused by susceptible Gram-positive bacteria.Flucloxacillin is a narrow-spectrum, semisynthetic isoxazolyl penicillin with antibacterial activity. Floxacillin binds to and inactivates penicillin-binding proteins (PBPs) located on the inner membrane of the bacterial cell wall. Inactivation of PBPs interferes with the cross-linkage of peptidoglycan chains necessary for bacterial cell wall strength and rigidity. This interrupts bacterial cell wall synthesis and results in the weakening of the bacterial cell wall, eventually causing cell lysis.

Mechanism of Action of Flucloxacillin

Flucloxacillin is a penicillin beta-lactam antibiotic used in the treatment of bacterial infections caused by susceptible, usually gram-positive, organisms. The name “penicillin” can either refer to several variants of penicillin available, or to the group of antibiotics derived from the penicillins. Flucloxacillin has in vitro activity against gram-positive and gram-negative aerobic and anaerobic bacteria. The bactericidal activity of Flucloxacillin results from the inhibition of cell wall synthesis and is mediated through flucloxacillin binding to penicillin binding proteins (PBPs). Flucloxacillin is stable against hydrolysis by a variety of beta-lactamases, including penicillinases, and cephalosporinases and extended spectrum beta-lactamases.By binding to specific penicillin-binding proteins (PBPs) located inside the bacterial cell wall, flucloxacillin inhibits the third and last stage of bacterial cell wall synthesis. Cell lysis is then mediated by bacterial cell wall autolytic enzymes such as autolysins; it is possible that flucloxacillin interferes with an autolysin inhibitor.

Or

By binding to specific penicillin-binding proteins (PBPs) located inside the bacterial cell wall, flucloxacillin inhibits the third and last stage of bacterial cell wall synthesis. Cell lysis is then mediated by bacterial cell wall autolytic enzymes such as autolysins; it is possible that flucloxacillininterferes with an autolysin inhibitor.

Indications of Flucloxacillin

It is most commonly used to treat infections.

  • Chest, ear, nose and throat (e.g. tonsillitis, sinusitis, pneumonia)
  • Skin and soft tissue (e.g. boils, burns, wounds, abscesses, infected eczema, infected acne)
  • Staphylococcal skin infections and cellulitis – including impetigo, otitis externa, folliculitis, boils, carbuncles, and mastitis
  • Pneumonia 
  • Osteomyelitis, septic arthritis
  • Septicaemia
  • Empirical treatment for endocarditis
  • Surgical prophylaxis
  • Other infections including those of the heart (endocarditis), bones and joints (osteomyelitis), membranes of the brain (meningitis), guts (enteritis), blood (septicaemia), and the kidney, bladder or urethra
  • Lung abscess
  • Empyema
  • Respiratory tract infections:
  • Osteomyelitis
  • Enteritis
  • Endocarditis
  • Septicaemia
  • Meningitis
  • Urinary tract infection
  • Used to treat bacterial infection by susceptible microorganisms.
  • Other infections caused by flucloxacillin-sensitive organisms

Contra Indications of Flucloxacillin

  • History of severe hypersensitivity (e.g. anaphylactic reaction) to any other type of betalactam antibacterial agent (penicillins, monobactams and carbapenems).
  • Hemolytic anemia
  • Liver problems
  • Interstitial nephritis
  • Subacute cutaneous lupus erythematosus
  • Systemic lupus erythematosus
  • use should be avoided in pregnant or lactating women, and in children with developing teeth because they may result in permanent staining (dark yellow-gray teeth with a darker horizontal band that goes across the top and bottom rows of teeth), and possibly affect the growth of teeth and bones.

Dosage of Flucloxacillin

Strengths: 125 mg; 200 mg; 250 mg ;400 mg;500 mg,  875 mg   125 mg/5 mL; 50 mg/mL; 250 mg/5 mL; ; 200 mg/5 mL; 400 mg/5 mL; 600 mg;

Bacterial Endocarditis

American Heart Association (AHA) recommendations

  • Immediate-release: 2 g orally as a single dose 30 to 60 minutes prior to procedure

Helicobacter pylori Infection

Immediate-release

  • Dual Therapy: 1 g orally every 8 hours for 14 days in combination with lansoprazole
  • Triple Therapy: 1 g orally every 12 hours for 14 days in combination with clarithromycin and lansoprazole

Pneumonia

Immediate-release

  • Mild, moderate, or severe infection: 500 mg orally every 8 hours or 875 mg every 12 hours

IDSA and American Thoracic Society (ATS) recommendations, Pneumonia

  • Immediate-release: 1 g orally 3 times a day

Bronchitis

Immediate-release

  • Mild, moderate, or severe infection: 500 mg orally every 8 hours or 875 mg every 12 hours

Sinusitis

Immediate-release

  • Mild to moderate infection: 250 mg orally every 8 hours or 500 mg every 12 hours
  • Severe infection: 500 mg orally every 8 hours or 875 mg every 12 hours

Urinary Tract Infection

Immediate-release

  • Mild to moderate infection: 250 mg orally every 8 hours or 500 mg every 12 hours
  • Severe infection: 500 mg orally every 8 hours or 875 mg every 12 hours

Tonsillitis/Pharyngitis

Extended-release

  • 775 mg orally once a day within 1 hour after a meal for 10 days

IDSA recommendations

  • Immediate-release: 1000 mg orally once a day or 500 mg orally twice a day

Skin and Structure Infection

Immediate-release

  • Mild to moderate infection: 250 mg orally every 8 hours or 500 mg every 12 hours
  • Severe infection: 500 mg orally every 8 hours or 875 mg every 12 hours

IDSA recommendations

  • Immediate-release: 500 mg orally 3 times a day for 7 to 10 days

Pediatric 

Sinusitis

Immediate-Release Formulations ,Mild, Moderate, or Severe Infection

  • 3 months or younger: Up to 30 mg/kg/day orally in divided doses every 12 hours

Immediate-Release Formulations, Mild to Moderate Infection ,4 months or older

  • Less than 40 kg: 20 mg/kg/day orally in divided doses every 8 hours or 25 mg/kg/day in divided doses every 12 hours
  • At least 40 kg: 250 mg orally every 8 hours or 500 mg every 12 hours

Severe Infection, 4 months or older

  • Less than 40 kg: 40 mg/kg/day orally in divided doses every 8 hours or 45 mg/kg/day in divided doses every 12 hours
  • At least 40 kg: 500 mg orally every 8 hours or 875 mg every 12 hours

Skin or Soft Tissue Infection

Immediate-Release Formulations , Mild, Moderate, or Severe Infection
3 months or younger: Up to 30 mg/kg/day orally in divided doses every 12 hours

Immediate-Release Formulations,Mild to Moderate Infection ,4 months or older

  • Less than 40 kg: 20 mg/kg/day orally in divided doses every 8 hours or 25 mg/kg/day in divided doses every 12 hours
  • At least 40 kg: 250 mg orally every 8 hours or 500 mg every 12 hours

Severe Infection, 4 months or older

  • Less than 40 kg: 40 mg/kg/day orally in divided doses every 8 hours or 45 mg/kg/day in divided doses every 12 hours
  • At least 40 kg: 500 mg orally every 8 hours or 875 mg every 12 hours

Urinary Tract Infection

  • Immediate-Release Formulations, Mild, Moderate, or Severe Infection
  • 3 months or younger: Up to 30 mg/kg/day orally in divided doses every 12 hours

Side Effects of Flucloxacillin

The most common side effects 

More common

Rare

Drug Interactions of  Flucloxacillin

Flucloxacillin may interact with following drugs, supplements, & may change the efficacy of drugs

Pregnancy & Lactation of Flucloxacillin

FDA Pregnancy Category B

Pregnancy

Animal studies with flucloxacillin have shown no teratogenic effects. The product has been in clinical use since 1970 and the limited number of reported cases of use in human pregnancy have shown no evidence of untoward effects. The decision to administer any drug during pregnancy should be taken with the utmost care. Therefore flucloxacillin should only be used in pregnancy when the potential benefits outweigh the potential risks associated with treatment.

Lactation

Trace quantities of flucloxacillin can be detected in breast milk. The possibility of hypersensitivity reactions must be considered in breastfeeding infants. Therefore flucloxacillin should only be administered to a breastfeeding mother when the potential benefits outweigh the potential risks associated with the treatment.

References