Flucloxacillin Health Dictionary

The name given by Sir Alexander Fleming, in 1929, to an antibacterial substance produced by the mould Penicillium notatum. The story of penicillin is one of the most dramatic in the history of medicine, and its introduction into medicine initiated a new era in therapeutics comparable only to the introduction of ANAESTHESIA by Morton and Simpson and of ANTISEPTICS by Pasteur and Lister. The two great advantages of penicillin are that it is active against a large range of bacteria and that, even in large doses, it is non-toxic. Penicillin di?uses well into body tissues and ?uids and is excreted in the urine, but it penetrates poorly into the cerebrospinal ?uid.

Penicillin is a beta-lactam antibiotic, one of a group of drugs that also includes CEPHALOSPORINS. Drugs of this group have a four-part beta-lactam ring in their molecular structure and they act by interfering with the cell-wall growth of mutliplying bacteria.

Among the organisms to which it has been, and often still is, active are: streptococcus, pneumococcus, meningococcus, gonococcus, and the organisms responsible for syphilis and for gas gangrene (for more information on these organisms and the diseases they cause, refer to the separate dictionary entries). Most bacteria of the genus staphylococcus are now resistant because they produce an enzyme called PENICILLINASE that destroys the antibiotic. A particular problem has been the evolution of strains resistant to methicillin – a derivative originally designed to conquer the resistance problem. These bacteria, known as METHICILLINRESISTANT STAPHYLOCOCCUS AUREUS (MRSA), are an increasing problem, especially after major surgery. Some are also resistant to other antibiotics such as vancomycin.

An important side-e?ect of penicillins is hypersensitivity which causes rashes and sometimes ANAPHYLAXIS, which can be fatal.

Forms of penicillin These include the following broad groups: benzylpenicillin and phenoxymethyl-penicillin; penicillinase-resistant penicillins; broad-spectrum penicillins; antipseudomonal penicillins; and mecillinams. BENZYLPENICILLIN is given intramuscularly, and is the form that is used when a rapid action is required. PHENOXYMETHYLPENICILLIN (also called penicillin V) is given by mouth and used in treating such disorders as TONSILLITIS. AMPICILLIN, a broad-spectrum antibiotic, is another of the penicillins derived by semi-synthesis from the penicillin nucleus. It, too, is active when taken by mouth, but its special feature is that it is active against gram-negative (see GRAM’S STAIN) micro-organisms such as E. coli and the salmonellae. It has been superceded by amoxicillin to the extent that prescriptions for ampicillin written by GPs in the UK to be dispensed to children have fallen by 95 per cent in the last ten years. CARBENICILLIN, a semi-synthetic penicillin, this must be given by injection, which may be painful. Its main use is in dealing with infections due to Pseudomonas pyocanea. It is the only penicillin active against this micro-organism which can be better dealt with by certain non-penicillin antibiotics. PIPERACILLIN AND TICARCILLIN are carboxypenicillins used to treat infections caused by Pseudomonas aeruginosa and Proteus spp. FLUCLOXACILLIN, also a semi-synthetic penicillin, is active against penicillin-resistant staphylococci and has the practical advantage of being active when taken by mouth. TEMOCILLIN is another penicillinase-resistant penicillin, e?ective against most gram-negative bacteria. AMOXICILLIN is an oral semi-synthetic penicillin with the same range of action as ampicillin but less likely to cause side-effects. MECILLINAM is of value in the treatment of infections with salmonellae (see FOOD POISONING), including typhoid fever, and with E. coli (see ESCHERICHIA). It is given by injection. There is a derivative, pivmecillinam, which can be taken by mouth. TICARCILLIN is a carboxypenicillin used mainly for serious infections caused by Pseudomonas aeruginosa, though it is also active against some gram-negative bacilli. Ticarcillin is available only in combination with clarulanic acid.... penicillin

An infectious skin disease caused usually by Staphylococcus aureus and less often by Streptococcus pyogenes. The itching rash is seen especially on the face but may spread widely. Vesicles and pustules erupt and dry to form yellow-brown scabs. Untreated, the condition may last for weeks. In very young infants, large blisters may form (bullous impetigo).

Treatment Crusts should be gently removed with SALINE. Mild cases respond to frequent application of mupiricin or NEOMYCIN/BACITRACIN ointment; more severe cases should be treated orally or, sometimes, intravenously with FLUCLOXACILLIN or one of the CEPHALOSPORINS. If the patient is allergic to penicillin, ERYTHROMYCIN can be used.

For severe, intractable cases, an oral retinoid drug called isotretinoin (commercially produced as Roaccutane®) can be used. It is given systemically but treatment must be supervised by a consultant dermatologist as serious side-effects, including possible psychiatric disturbance, can occur. The drug is also teratogenic (see TERATOGENESIS), so women who are, or who may become, pregnant must not take isotretinoin. It acts mainly by suppressing SEBUM production in the sebaceous glands and can be very e?ective. Recurrent bouts of impetigo should raise suspicion of underlying SCABIES or head lice. Bactericidal soaps and instilling an antibiotic into the nostrils may also help.... impetigo

The term applied to in?ammation near the nail (see under SKIN). The infection, usually caused by Staphyloccous aureus (see STAPHYLOCOCCUS), may affect the tissues around the nail, including its root, and sometimes spreads to the pulp of the affected ?nger or toe. The tendons that run along the back of the infected digit may occasionally become infected. Acute paronychia is the most common type, with local pain and tenderness and swelling of the nail fold. Treatment is with ANTIBIOTICS or, if an ABSCESS forms, local surgery to release any pus. Sometimes infection may be caused by a virus, against which antibiotics are ine?ective. If viral infection persists then antiviral drugs may eradicate it.

Chronic paronychia occurs with reinfection of the nail bed. This is usually because the person’s hands are regularly immersed in water, making the skin vulnerable to infection. The ?nger should be kept dry and a dry dressing applied accompanied by a course of antibiotics

– FLUCLOXACILLIN or a cephalosporin.... paronychia

(methicillin) n. a semisynthetic penicillin that was originally used to treat infections by penicillin-resistant staphylococci. It has been superseded for this purpose by *flucloxacillin but continues to be used to test the drug sensitivity of staphylococci. Meticillin-resistant staphylococci (MRS) can be responsible for increasing rates of infection in hospitals. Until recently, such infections have responded to *vancomycin, but strains of bacilli have emerged that are resistant to vancomycin, giving rise to infections that are very difficult to treat. See also superinfection.... meticillin