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Cefaclor modified release tablets

Updated 2 Feb 2023 | Cephalosporins


Modified release tablets containing cefaclor (as cefaclor monohydrate)

Drugs List

  • cefaclor 375mg modified release tablet
  • DISTACLOR 375mg modified release tablet
  • Therapeutic Indications


    Antibiotic sensitive infections

    Treatment of the following infections when caused by specific organisms:
    Acute bronchitis and acute exacerbations of chronic bronchitis caused by Streptococcus pneumoniae, Haemophilus influenzae, Haemophilus parainfluenzae, Moraxella catarrhalis and Staphylococcus aureus.

    Pharyngitis and tonsillitis caused by Streptococcus pyogenes.

    Pneumonia caused by S. pneumoniae, H. influenzae and M. catarrhalis.

    Uncomplicated lower urinary tract infections, including cystitis and asymptomatic bacteriuria caused by Escherichia coli, Klebsiella pneumoniae, Proteus mirabilis and Staphylococcus saprophyticus.

    Skin and skin structure infections caused by S.pyogenes, S.aureus and Staphylococcus epidermidis.

    Cefaclor is usually effective in eradication streptococci from the oropharynx. However, it is not known if cefaclor is effective in the subsequent prevention of rheumatic fever.


    Consult national or regional policy on the use of anti-infectives.


    Pharyngitis, tonsillitis, skin infections
    375mg twice daily.
    In the treatment of infections caused by S. pyogenes (group A streptococci), a therapeutic dose should be administered for at least 10 days.

    Lower urinary tract infections
    375mg twice daily or 500mg once daily.

    375mg or 500mg twice daily.

    750mg twice daily.

    In clinical trials, doses of 1.5g daily have been administered for 14 days. Doses of 4g daily have been administered safely, to normal subjects, for 28 days.


    The manufacturer suggests that safety and effectiveness of cefaclor modified release has not been established in children. Cefaclor suspension and capsules are available.

    In the treatment of infections caused by S. pyogenes (group A streptococci), a therapeutic dose should be administered for at least 10 days.

    Children aged 12 to 18 years old (unlicensed)
    Susceptible infections
    375mg twice daily.

    750mg twice daily.

    Lower urinary-tract infections
    375mg twice daily.


    Children under 12 years

    Precautions and Warnings

    Children aged 12 to 18 years
    Renal impairment

    Before initiating therapy enquire about previous hypersensitivity reactions
    Consult national/regional policy on the use of anti-infectives
    Advise patient to take with or after food
    Discontinue treatment if patient develops seizures
    Consider pseudomembranous colitis if patient presents with diarrhoea
    Prolonged use may result in superinfection with non-susceptible organisms
    May affect results of some laboratory tests
    Discontinue at once if pseudomembranous colitis occurs
    Discontinue if drug-related rash or other hypersensitivity reactions occur

    Pregnancy and Lactation


    Use cefaclor with caution during pregnancy.

    Schaefer suggests cephalosporins can be used safely during pregnancy if required. Briggs suggests use of cefaclor during pregnancy is compatible. No teratogenic risks have been detected in numerous animal studies and one large human study. The manufacturer suggests modified release cefaclor should only be used during pregnancy when clearly needed.

    Animal studies have shown no evidence of impaired fertility or foetal harm due to cefaclor. At the time of writing, there are limited data available in pregnant women.

    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 ( ) or if this is unavailable at the backup site ( ).


    Use cefaclor with caution during breastfeeding.

    The Drugs and Lactation Database (LactMed) suggests cefaclor can be used during breastfeeding. Occasional disruption of the infant's gastrointestinal flora resulting in diarrhoea or thrush has been reported with cephalosporins but the effects have not been adequately evaluated. The manufacturer suggests caution should be exercised if administering to breastfeeding women.

    Small amounts of cefaclor have been detected in breast milk following administration of single 500 mg doses. Average levels of 0.2 micrograms/ml were detected up to 5 hours after cefaclor administration. Trace amounts were detected after one hour.

    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

    Side Effects

    Abdominal discomfort
    Aplastic anaemia
    Cholestatic jaundice
    Erythema multiforme
    Facial oedema
    Genital pruritus
    Haemolytic anaemia
    Hepatic impairment
    Hypersensitivity reactions
    Increase in alkaline phosphatase
    Increase in blood urea nitrogen
    Increase in serum ALT/AST
    Interstitial nephritis
    Monilia vaginitis
    Oedema of the extremities (arms and legs)
    Positive Coombs test
    Possible alteration of laboratory tests
    Pseudomembranous colitis
    Renal impairment
    Serum creatinine increased
    Serum sickness-like reactions
    Stevens-Johnson syndrome
    Toxic epidermal necrolysis
    Toxic nephropathies

    Effects on Laboratory Tests

    A false-positive reaction for glucose in the urine may occur with Benedict's or Fehling's solutions or with copper sulfate test tablets.

    Positive direct Coombs' test have been reported with cefaclor therapy.


    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 ( ) or if this is unavailable at the backup site ( ).

    Further Information

    Last Full Review Date: October 2015

    Reference Sources

    Drugs During Pregnancy and Lactation: Treatment Options and Risk Assessment, 2nd edition (2007) ed. Schaefer, C., Peters, P. and Miller, R. Elsevier, London.

    Drugs in Pregnancy and Lactation: A Reference Guide to Fetal and Neonatal Risk, 9th edition (2011) ed. Briggs, G., Freeman, R. and Yaffe, S. Lippincott Williams & Wilkins, Philadelphia.

    Summary of Product Characteristics: Distaclor MR. Flynn Pharma Ltd. Revised September 2015.

    NICE Evidence Services Available at: Last accessed: 15 August 2017

    US National Library of Medicine. Toxicology Data Network. Drugs and Lactation Database (LactMed).
    Available at:
    Cefaclor. Last revised: 10 March 2015.
    Last accessed: 14 October 2015.

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