Products
Flucloxacillin is commercially available in capsule form and as an injectable (floxapen, generic). It has been approved in many countries since 1972.
Structure and properties
Flucloxacillin (C19H17ClFN3O5S, Mr = 453.9 g/mol) is present in drugs as the sodium salt flucloxacillin sodium, a white, crystalline, and hygroscopic powder that is readily soluble in water. Flucloxacillin is fluorochloro-oxacillin. Cloxacillin (chloro-oxacillin, without fluorine) is also commercially available in many countries, but exclusively as a veterinary drug.
Effects
Flucloxacillin (ATC J01CF05) has bacteriostatic or bactericidal properties. It is effective against Gram-positive pathogens such as staphylococci and streptococci. Unlike other penicillins such as amoxicillin, it is resistant to β-lactamases. Its effects are based on inhibition of bacterial cell wall synthesis by inhibition of transpeptidases involved in the synthesis of peptidoglycan.
Indications
Flucloxacillin is approved in many countries for the treatment of infections with penicillinase-producing staphylococci. These include bacterial infectious diseases such as respiratory tract infections, urinary tract infections, and skin infections.
Dosage
According to the SmPC. Flucloxacillin is taken one-half to one hour before eating because this may increase absorption.
Contraindications
Flucloxacillin is contraindicated in hypersensitivity to penicillins or cephalosporins, jaundice, or liver dysfunction, among other conditions. For complete precautions and interactions, see the drug label.
Interactions
Flucloxacillin is an organic anion; therefore, its renal elimination from probenecid is reduced, which may result in increased blood levels. Flucloxacillin may reduce the effectiveness of oral contraceptives.
Adverse Effects
The most common adverse effects include digestive disturbances such as nausea, vomiting, diarrhea, and abdominal pain. Occasionally, skin rashes of varying severity, including itching, occur. Other, less frequent adverse effects are possible. Possible very rare and severe adverse reactions include hepatitis, cholestasis, renal dysfunction, blood count abnormalities, and severe skin reactions.
