- Drugs List
- Therapeutic Indications
- Precautions and Warnings
- Pregnancy and Lactation
- Side Effects
Parenteral formulations of flucloxacillin.
Infections due to Gram-positive organisms incl. penicillin-resistant staph.
Prophylaxis against infections in major surgery
Respiratory tract infections - upper and lower
Staphylococcal lung infection in cystic fibrosis - treatment
Flucloxacillin dosage is dependent on the age, weight and renal function of the patient, as well as the nature and severity of the infection.
250mg to be administered four times per day. This dose may be doubled where necessary.
250mg to 1g to be administered four times per day. This dose may be doubled where necessary.
250mg once daily.
250mg to 500mg once daily.
Inhalation via nebuliser
125mg to 250mg four times per day.
Up to 8g daily in three to four divided doses.
Endocarditis (usually in combination with another antibacterial)
Bodyweight under 85kg: 8g daily in four divided doses.
Bodyweight equal to or greater than 85kg: 12g daily in six divided doses (unlicensed).
Prophylaxis of infection during major surgical procedures
Initial dose: 1g to 2g to be administered intravenously at induction of anaesthesia.
Maintenance dose: 500mg every 6 hours to be administered intravenously, intramuscularly, or orally for up to 72 hours post-surgery.
Children over 10 years: 100% of adult dose.
Children aged 2 to 10 years: 50% of adult dose.
Children aged under 2 years: 25% of adult dose.
The following alternative dosing schedules may be suitable:
Infections due to beta-lactamase producing staphylococci including otitis externa, adjunct in pneumonia, impetigo, cellulitis
12.5mg/kg to 25mg/kg every 6 hours. Maximum dose of 500mg every 6 hours.
12.5mg/kg to 25mg/kg every 6 hours. Maximum dose of 1g every 6 hours. This dose may be doubled in severe infections.
Cerebral abscess; Endocarditis; Osteomyelitis; Staphylococcal lung infection in cystic fibrosis; Staphylococcal meningitis
50mg/kg every 6 hours intravenously. Maximum dose of 2g every 6 hours.
Treatment of infections due to beta-lactamase producing staphylococci including otitis externa, adjunct in pneumonia, impetigo, cellulitis
Neonate aged 21 to 28 days: 25mg/kg every 6 hours. May be doubled in severe infection.
Neonate aged 7 to 20 days: 25mg/kg every 8 hours. May be doubled in severe infection.
Neonate aged under 7 days: 25mg/kg every 12 hours. May be doubled in severe infection.
Cerebral abscess; Osteomyelitis; Staphylococcal meningitis
Neonate aged 21 to 28 days old: 50mg/kg to 100mg/kg every 6 hours.
Neonate aged 7 to 20 days old: 50mg/kg to 100mg/kg every 8 hours.
Neonate aged under 7 days old: 50mg/kg to 100mg/kg every 12 hours.
Patients with Renal Impairment
Severe renal impairment (creatinine clearance less than 10ml per minute)
Dose as normal, up to a maximum of 4g daily.
History of hepatic impairment due to previous use of this drug
History of jaundice due to previous use of this drug
Precautions and Warnings
Patients over 50 years
Renal impairment - creatinine clearance below 10ml/minute
Jarisch-Herxheimer reaction possible in treatment of syphilis
Reduce dose and/or alter dose interval in patients with renal impairment
Some formulations contain more than 1mmol (23mg) sodium per dose
Before initiating therapy enquire about previous hypersensitivity reactions
Consult national/regional policy on the use of anti-infectives
Avoid contact of product with skin
For single use only
Monitor haematological status during prolonged and high dose therapy
Monitor hepatic function on long term therapy
Monitor renal function during prolonged/high dose therapy
Cholestatic jaundice may occur during or after treatment
Consider pseudomembranous colitis if patient presents with diarrhoea
Prolonged use may result in superinfection with non-susceptible organisms
May affect urine protein dipstick test
May cause false positive Coomb's test and glycosuria test
Discontinue at once if pseudomembranous colitis occurs
Discontinue if drug-related rash or other hypersensitivity reactions occur
Advise patient to seek medical advice before taking paracetamol products
In patients over 50 years old hepatic events may be more severe, and on rare occasion have been fatal.
Neurological disorders, such as convulsions, may occur following intravenous administration of high doses to patients with renal failure.
Pregnancy and Lactation
In pregnancy flucloxacillin should only be used with caution and with monitoring of the infant.
No embryotoxicity resulting from Flucloxacillin use during pregnancy has been found in the limited number of studies on the drug. Animal studies have shown no teratogenic effects. The manufacturer states that this product should be used with caution in pregnancy.
Flucloxacillin is known to cross the placenta, and can be detected in the amniotic fluid. The effects of this on the foetus are unknown.
The use of all medication in pregnancy should be avoided whenever possible; particularly in the first trimester. Non-drug treatments should also be considered. When essential, a medication with the best safety record over time should be chosen, employing the lowest effective dose for the shortest possible time. Polypharmacy should be avoided. Teratogens taken in the pre-embryonic period, often quoted as lasting until 14 to 17 days post-conception, are believed to have an all-or-nothing effect. Where drugs have a short half-life, and when the date of conception is certain, this may allow women to be reassured where drug exposure has occurred within this time frame. Further advice may be available from the UK National Teratology Information Service (NTIS) and through ToxBase, available via password on the internet ( www.toxbase.org ) or if this is unavailable at the backup site ( www.toxbasebackup.org ).
Use flucloxacillin with caution in breastfeeding.
The manufacturer states that this drug must be used with caution during breastfeeding. Limited amounts of flucloxacillin are known to be present in breast milk, however Lactmed suggests the amount of the drug present in breast milk is unlikely to cause adverse effects in breastfed infants.
Neonates, infants born prematurely, those with low birth weight, those with an unstable gastrointestinal function or who have serious illnesses may require special consideration. For any infant, if a drug is prescribed to the nursing mother, it should be at the lowest practical dose and for the shortest time. When drug administration is unavoidable and breastfeeding is to continue, minimisation of exposure of the infant to the drug may sometimes be achieved by timing the maternal doses to just after a feeding episode. Infants exposed to drugs via breast milk should be monitored for unusual signs or symptoms. Interactions between the drug received by the infant from the mother's milk and medication prescribed for the infant should also be considered, for example, when the drug given to the infant may prevent metabolism of the drug received via breast milk.
Specialist advice is available from the UK Drugs in Lactation Advisory Service at https://www.midlandsmedicines.nhs.uk/content.asp?section=6&subsection=17&pageIdx=1
Acute generalised exanthematous pustulosis
Altered liver function tests
Candidiasis (mouth or throat)
Impaired platelet function
Nervous system effects
Serum sickness-like reactions
Toxic epidermal necrolysis
It is strongly recommended that the UK National Poisons Information Service be consulted on cases of suspected or actual overdose where there is doubt over the degree of risk or about appropriate management.
The following number will direct the caller to the relevant local centre (0844) 892 0111
Information may be obtained if you have access to ToxBase the primary clinical toxicology database of the National Poisons Information Service. This is available via password on the internet ( www.toxbase.org ) or if this is unavailable at the backup site ( www.toxbasebackup.org ).
Last Full Review Date: March 2018
Drugs During Pregnancy and Lactation: Treatment Options and Risk Assessment, 3rd edition (2015) ed. Schaefer, C., Peters, P. and Miller, R. Elsevier, London.
Summary of Product Characteristics: Flucloxacillin for Injection 2g. Bowmed Ibisqus Ltd. Revised December 2017.
Summary of Product Characteristics: Flucloxacillin for Injection 250mg. Wockhardt UK Ltd. Revised January 2018.
Summary of Product Characteristics: Flucloxacillin for Injection 500mg. Wockhardt UK Ltd. Revised January 2018.
Summary of Product Characteristics: Flucloxacillin for Injection 1g. Wockhardt UK Ltd. Revised January 2018.
The Renal Drug Handbook. Fourth Edition (2014) ed. Ashley, C and Dunleavy, A, Radcliffe Publishing Ltd, London.
US National Library of Medicine. Toxicology Data Network. Drugs and Lactation Database (LactMed).
Available at: https://toxnet.nlm.nih.gov/cgi-bin/sis/htmlgen?LACT
Flucloxacillin Last revised: 09 March 2018
Last accessed: 15 March 2018
NICE Evidence Services Available at: www.nice.org.uk Last accessed: 15 March 2018
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Medscape UK | Univadis prescription drug monographs & interactions are based on FDB Multilex Content
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