CEFALEXIN

Adults The adult dosage ranges from 1-4g daily in divided doses; most infections will respond to a dosage of 500mg every 8 hours. For skin and soft tissue infections, streptococcal pharyngitis and mild, uncomplicated urinary tract infections, the usual dosage is 250mg every 6 hours, or 500mg every 12 hours.

For more severe infections or those caused by less susceptible organisms, larger doses may be needed. If daily doses of cefalexin greater than 4g are required parenteral cephalosporins, in appropriate doses, should be considered. Elderly As for adults.

4). Children The usual recommended daily dosage for children is 25-50mg/kg (10- 20mg/lb) in divided doses. For skin and soft tissue infections, streptococcal pharyngitis and mild, uncomplicated urinary tract infections, the total daily dose may be divided and administered every 12 hours.

For most infections the following schedule is suggested:

Children under 5 years: 125mg every 8 hours. Children 5 years and over: 250mg every 8 hours. In severe infections, the dosage may be doubled. In the therapy of otitis media, clinical studies have shown that a dosage of 75-100mg/kg/day in 4 divided doses is required.

In the treatment of beta-haemolytic streptococcal infections, a therapeutic dose should be administered for at least 10 days. Route of administration Oral

Gastro-intestinal-nausea, vomiting, dyspepsia, and abdominal pain have occurred. Diarrhoea has been reported infrequently. It is rarely severe enough to warrant cessation of therapy. Colitis, including rare instances of pseudomembranous colitis, has been reported.

Hypersensitivity - Allergies (in the form of rash, urticaria and angio- oedema), and rarely erythema multiforme, Stevens-Johnson syndrome and toxic epidermal necrolysis have been observed. These reactions usually subside upon discontinuation of the drug, although in some cases supportive therapy may be necessary.

Anaphylaxis has also been reported. Heamic and Lymphatic System: - eosinophilia, neutropenia, thrombocytopenia and haemolytic anaemia have been reported. Hepatic - slight elevations of AST and ALT have been observed. As with some penicillins and some other cephalosporins, transient hepatitis and cholestatic jaundice have been reported rarely.

Skin and subcutaneous tissue disorders:

Acute generalised exanthematous pustulosis (AGEP) has been reported with unknown frequency. Other: - other reactions have included genital and anal pruritus, genital moniliasis, vaginitis and vaginal discharge, dizziness, fatigue, headache, agitation, confusion, hallucinations, arthralgia, arthritis and joint disorder.

Reversible interstitial nephritis has been reported rarely. There have been reports of neurological sequelae including tremor, myoclonia, convulsions, encephalopathy with drugs belonging to the class of cephalosporins. Most cases occurred in patients with renal impairment who received doses that exceeded the recommended dose and resolved following discontinuation of treatment.

Reporting of suspected adverse reactions Reporting suspected adverse reactions after authorisation of the medicinal product is important. uk/yellowcard or search for MHRA Yellow Card in the Google Play or Apple App Store.

Before instituting therapy with cefalexin, every effort should be made to determine whether the patient has had previous hypersensitivity reactions to the cephalosporins, penicillins or other drugs. Cefalexin should be given cautiously to penicillin-sensitive patients.

There is some clinical and laboratory evidence of partial cross-allergenicity of the penicillins and cephalosporins. Patients have had severe reactions (including anaphylaxis) to both drugs. Pseudomembranous colitis has been reported with virtually all broad-spectrum antibiotics, including macrolides, semisynthetic penicillins and cephalosporins.

It is important, therefore, to consider its diagnosis in patients who develop diarrhoea in association with the use of antibiotics. Such colitis may range in severity from mild to life-threatening. Mild cases of pseudomembranous colitis usually respond to drug discontinuance alone.

In moderate to severe cases, appropriate measures should be taken. If an allergic reaction to cefalexin occurs the drug should be discontinued and the patient treated with the appropriate agents. Prolonged use of cefalexin may result in the overgrowth of non-susceptible organisms.

Careful observation of the patient is essential. If superinfection occurs during therapy, appropriate measures should be taken. Reports of neurotoxicity have been identified in association with cephalosporin treatment. Symptoms may include encephalopathy, myoclonus and seizures.

Elderly patients, patients with severe renal impairment or central nervous system disorders are particularly at risk. Cefalexin should be administered with caution in the presence of markedly impaired renal function. Careful clinical and laboratory studies should be made because safe dosage may be lower than that usually recommended.

If dialysis is required for renal failure, the daily dose of cefalexin should not exceed 500mg. If cefalexin associated neurotoxicity is suspected, discontinuation of cefalexin should be considered. Concurrent administration with certain other drug substances, such as aminoglycosides, other cephalosporins, or furosemide, (frusemide) and similar potent diuretics, may increase the risk of nephrotoxicity.

Positive direct Coombs' tests have been reported during treatment with the cephalosporin antibiotics. In haematological studies, or in transfusion cross- matching procedures when antiglobulin tests are performed on the minor side, or in Coombs' testing of newborns whose mothers have received cephalosporin antibiotics before parturition, it should be recognised that a positive Coombs' test may be due to the drug.

A false positive reaction for glucose in the urine may occur with Benedict's or Fehling's solutions or with copper sulphate test tablets. Acute generalised exanthematous pustulosis (AGEP) has been reported in association with cefalexin treatment.

At the time of prescription patients should be advised of the signs and symptoms and monitored closely for skin reactions. If signs and symptoms suggestive of these reactions appear, cefalexin should be withdrawn immediately and an alternative treatment considered.

Most of these reactions occurred most likely in the first week during treatment. Excipients Cefalexin capsules contains lactose and therefore should not be used in patients with rare hereditary problems of fructose intolerance, galactose intolerance, galactosaemia or glucose-galactose malabsorption should not take this medicine.

Cefalexin is contraindicated in patients with known allergy to the cephalosporins group of antibiotics. Cefalexin should be given cautiously to patients who have shown hypersensitivity to other drugs. Cephalosporins should be given with caution to penicillin-sensitive patients, as there is some evidence of partial cross- allergenicity between the penicillins and the cephalosporins.

Patients have had severe reactions (including anaphylaxis) to both drugs. Cefalexin is contraindicated in patients with porphyria.