Cefaclor Dosage

Medically reviewed by Drugs.com. Last updated on Jan 21, 2025.

Usual Adult Dose for Upper Respiratory Tract Infection

Immediate release (IR) formulations: 250 to 500 mg orally every 8 hours
Duration of therapy:

• Empirical treatment: At least 48 to 72 hours after the patient becomes asymptomatic OR bacterial eradication evidence is obtained
• Acute bacterial sinusitis: 10 days
• Group A streptococcal (GAS) infections: At least 10 days

Extended release (ER) tablets: 500 mg orally every 12 hours

• Maximum dose: 1000 mg/day
• Duration of therapy: 7 days

Comments:

• ER tablets given 500 mg orally 2 times a day are only clinically equivalent to IR capsule formulations given 250 mg orally 3 times a day.
• IR formulations: Doses up to 500 mg may be used to treat more severe infections OR infections caused by less susceptible organisms.
• Infections caused by beta-lactamase-negative, ampicillin-resistant (BLNAR) Haemophilus influenzae should be considered resistant to this drug.

Uses:

• Treatment of mild to moderate acute bacterial exacerbations of chronic bronchitis due to H influenzae (only non-beta-lactamase-producing strains), Moraxella catarrhalis (including beta-lactamase-producing strains), or Streptococcus pneumoniae
• Treatment of mild to moderate secondary bacterial infection of acute bronchitis due to H influenzae (only non-beta-lactamase-producing strains), M catarrhalis (including beta-lactamase strains), or S pneumoniae

Usual Adult Dose for Bronchitis

Immediate release (IR) formulations: 250 to 500 mg orally every 8 hours
Duration of therapy:

• Empirical treatment: At least 48 to 72 hours after the patient becomes asymptomatic OR bacterial eradication evidence is obtained
• Acute bacterial sinusitis: 10 days
• Group A streptococcal (GAS) infections: At least 10 days

Extended release (ER) tablets: 500 mg orally every 12 hours

• Maximum dose: 1000 mg/day
• Duration of therapy: 7 days

Comments:

• ER tablets given 500 mg orally 2 times a day are only clinically equivalent to IR capsule formulations given 250 mg orally 3 times a day.
• IR formulations: Doses up to 500 mg may be used to treat more severe infections OR infections caused by less susceptible organisms.
• Infections caused by beta-lactamase-negative, ampicillin-resistant (BLNAR) Haemophilus influenzae should be considered resistant to this drug.

Uses:

• Treatment of mild to moderate acute bacterial exacerbations of chronic bronchitis due to H influenzae (only non-beta-lactamase-producing strains), Moraxella catarrhalis (including beta-lactamase-producing strains), or Streptococcus pneumoniae
• Treatment of mild to moderate secondary bacterial infection of acute bronchitis due to H influenzae (only non-beta-lactamase-producing strains), M catarrhalis (including beta-lactamase strains), or S pneumoniae

Usual Adult Dose for Otitis Media

IR formulations: 250 to 500 mg orally every 8 hours
Duration of therapy:

• Empirical treatment: At least 48 to 72 hours after the patient becomes asymptomatic OR bacterial eradication evidence is obtained
• Acute bacterial sinusitis: 10 days
• GAS infections: At least 10 days

Comments:

• Infections caused by BLNAR H influenzae should be considered resistant to this drug.
• IR formulations: Doses up to 500 mg may be used to treat more severe infections OR infections caused by less susceptible organisms.

Use: Treatment of otitis media caused by H influenzae, staphylococci, S pneumoniae, and Streptococcus pyogenes

Usual Adult Dose for Pneumonia

IR formulations: 250 to 500 mg orally every 8 hours
Duration of therapy:

• Empirical treatment: At least 48 to 72 hours after the patient becomes asymptomatic OR bacterial eradication evidence is obtained
• Acute bacterial sinusitis: 10 days
• GAS infections: At least 10 days

Comments:

• IR formulations: Higher doses should be used to treat more severe infections OR infections caused by less susceptible organisms.
• IR formulations: Doses up to 500 mg may be used to treat more severe infections OR infections caused by less susceptible organisms.
• Infections caused by BLNAR H influenzae should be considered resistant to this drug.

Use: Treatment of lower respiratory tract infections, including pneumonia, caused by H influenzae, S pneumoniae, and S pyogenes

Usual Adult Dose for Skin and Structure Infection

IR formulations: 250 to 500 mg orally every 8 hours
Duration of therapy:

• Empirical treatment: At least 48 to 72 hours after the patient becomes asymptomatic OR bacterial eradication evidence is obtained
• Acute bacterial sinusitis: 10 days
• GAS infections: At least 10 days

ER tablets: 375 mg orally every 12 hours

• Maximum dose: 750 mg/day
• Duration of therapy: 7 to 10 days

Comments:

• Safety and efficacy in the treatment of skin infections known/potentially caused by S pyogenes with extended-release tablets are unknown.
• IR formulations: Doses up to 500 mg may be used to treat more severe infections OR infections caused by less susceptible organisms.

Uses:

• Treatment of mild to moderate uncomplicated skin and structure infections due to methicillin-susceptible Staphylococcus aureus (MSSA)
• Treatment of skin and structure infections caused by S aureus and S pyogenes

Usual Adult Dose for Tonsillitis/Pharyngitis

IR formulations: 250 to 500 mg orally every 8 hours
Duration of therapy:

• Empirical treatment: At least 48 to 72 hours after the patient becomes asymptomatic OR bacterial eradication evidence is obtained
• Acute bacterial sinusitis: 10 days
• GAS infections: At least 10 days

ER tablets: 375 mg orally every 12 hours

• Maximum dose: 750 mg/day
• Duration of therapy: 10 days

Comments:

• This drug is generally effective in eradicating nasopharynx and oropharynx infections caused by S pyogenes.
• IM penicillin is the only agent shown to be effective in the prophylaxis of rheumatic fever.
• IR formulations: Doses up to 500 mg may be used to treat more severe infections OR infections caused by less susceptible organisms.

Uses:

• Treatment of mild to moderate pharyngitis and tonsillitis due to S pyogenes
• Treatment of pharyngitis and tonsillitis caused by S pyogenes

Usual Adult Dose for Pyelonephritis

IR formulations: 250 to 500 mg orally every 8 hours
Duration of therapy:

• Empirical treatment: At least 48 to 72 hours after the patient becomes asymptomatic OR bacterial eradication evidence is obtained
• Acute bacterial sinusitis: 10 days
• GAS infections: At least 10 days

Comments:

• This drug is generally effective in eradicating nasopharynx and oropharynx infections caused by S pyogenes.
• IM penicillin is the only agent shown to be effective in the prophylaxis of rheumatic fever.
• IR formulations: Doses up to 500 mg may be used to treat more severe infections OR infections caused by less susceptible organisms.

Use: Treatment of urinary tract infections, including cystitis and pyelonephritis, caused by coagulase-negative staphylococci, Escherichia coli, Klebsiella species, and Proteus mirabilis

Usual Adult Dose for Urinary Tract Infection

IR formulations: 250 to 500 mg orally every 8 hours
Duration of therapy:

• Empirical treatment: At least 48 to 72 hours after the patient becomes asymptomatic OR bacterial eradication evidence is obtained
• Acute bacterial sinusitis: 10 days
• GAS infections: At least 10 days

Comments:

• This drug is generally effective in eradicating nasopharynx and oropharynx infections caused by S pyogenes.
• IM penicillin is the only agent shown to be effective in the prophylaxis of rheumatic fever.
• IR formulations: Doses up to 500 mg may be used to treat more severe infections OR infections caused by less susceptible organisms.

Use: Treatment of urinary tract infections, including cystitis and pyelonephritis, caused by coagulase-negative staphylococci, Escherichia coli, Klebsiella species, and Proteus mirabilis

Usual Pediatric Dose for Otitis Media

Children 1 month and older:
IR formulations: 20 mg to 40 mg/kg per day orally, given every 8 to 12 hours

• Maximum dose: 1 gram/day

Duration of therapy:

• Empirical treatment: At least 48 to 72 hours after the patient becomes asymptomatic OR bacterial eradication evidence is obtained
• Acute bacterial sinusitis: 10 days
• GAS infections: At least 10 days

16 years and older:
ER tablets: 375 mg orally every 12 hours

• Maximum dose: 750 mg/day
• Duration of therapy: 10 days

Comments:

• Efficacy has been established for otitis media and/or pharyngitis/tonsillitis in doses given every 12 hours.
• This drug is generally effective in eradicating oropharynx S pyogenes infections.
• IM penicillin is the only agent shown to be effective in the prophylaxis of rheumatic fever.
• IR formulations: Doses up to 40 mg/kg may be used to treat more severe infections OR infections caused by less susceptible organisms.
• Infections caused by BLNAR H influenzae should be considered resistant to this drug.

Uses:

• Treatment of otitis media caused by H influenzae, staphylococci, S pneumoniae, and S pyogenes
• Treatment of mild to moderate pharyngitis and tonsillitis due to S pyogenes

Usual Pediatric Dose for Tonsillitis/Pharyngitis

Children 1 month and older:
IR formulations: 20 mg to 40 mg/kg per day orally, given every 8 to 12 hours

• Maximum dose: 1 gram/day

Duration of therapy:

• Empirical treatment: At least 48 to 72 hours after the patient becomes asymptomatic OR bacterial eradication evidence is obtained
• Acute bacterial sinusitis: 10 days
• GAS infections: At least 10 days

16 years and older:
ER tablets: 375 mg orally every 12 hours

• Maximum dose: 750 mg/day
• Duration of therapy: 10 days

Comments:

• Efficacy has been established for otitis media and/or pharyngitis/tonsillitis in doses given every 12 hours.
• This drug is generally effective in eradicating oropharynx S pyogenes infections.
• IM penicillin is the only agent shown to be effective in the prophylaxis of rheumatic fever.
• IR formulations: Doses up to 40 mg/kg may be used to treat more severe infections OR infections caused by less susceptible organisms.
• Infections caused by BLNAR H influenzae should be considered resistant to this drug.

Uses:

• Treatment of otitis media caused by H influenzae, staphylococci, S pneumoniae, and S pyogenes
• Treatment of mild to moderate pharyngitis and tonsillitis due to S pyogenes

Usual Pediatric Dose for Cystitis

IR formulations: 20 mg 40 mg/kg per day orally, given every 8 to 12 hours

• Maximum dose: 1 gram/day

Duration of therapy:

• Empirical treatment: At least 48 to 72 hours after the patient becomes asymptomatic OR bacterial eradication evidence is obtained
• Acute bacterial sinusitis: 10 days
• GAS infections: At least 10 days

16 years and older:
ER tablets: 375 mg orally every 12 hours

• Maximum dose: 750 mg/day
• Duration of therapy: 7 to 10 days

Comments:

• This drug is generally effective in eradicating nasopharynx and oropharynx infections caused by S pyogenes.
• IM penicillin is the only agent shown to be effective in the prophylaxis of rheumatic fever.
• IR formulations: Doses up to 40 mg/kg may be used to treat more severe infections OR infections caused by less susceptible organisms.
• Infections caused by BLNAR H influenzae should be considered resistant to this drug.

Uses:

• Treatment of lower respiratory tract infections, including pneumonia, caused by H influenzae, S pneumoniae, and S pyogenes
• Treatment of mild to moderate uncomplicated skin and structure infections due to MSSA
• Treatment of skin and structure infections caused by S aureus and S pyogenes
• Treatment of urinary tract infections, including cystitis and pyelonephritis, caused by coagulase-negative staphylococci, E coli, Klebsiella species, and P mirabilis

Usual Pediatric Dose for Pneumonia

IR formulations: 20 mg 40 mg/kg per day orally, given every 8 to 12 hours

• Maximum dose: 1 gram/day

Duration of therapy:

• Empirical treatment: At least 48 to 72 hours after the patient becomes asymptomatic OR bacterial eradication evidence is obtained
• Acute bacterial sinusitis: 10 days
• GAS infections: At least 10 days

16 years and older:
ER tablets: 375 mg orally every 12 hours

• Maximum dose: 750 mg/day
• Duration of therapy: 7 to 10 days

Comments:

• This drug is generally effective in eradicating nasopharynx and oropharynx infections caused by S pyogenes.
• IM penicillin is the only agent shown to be effective in the prophylaxis of rheumatic fever.
• IR formulations: Doses up to 40 mg/kg may be used to treat more severe infections OR infections caused by less susceptible organisms.
• Infections caused by BLNAR H influenzae should be considered resistant to this drug.

Uses:

• Treatment of lower respiratory tract infections, including pneumonia, caused by H influenzae, S pneumoniae, and S pyogenes
• Treatment of mild to moderate uncomplicated skin and structure infections due to MSSA
• Treatment of skin and structure infections caused by S aureus and S pyogenes
• Treatment of urinary tract infections, including cystitis and pyelonephritis, caused by coagulase-negative staphylococci, E coli, Klebsiella species, and P mirabilis

Usual Pediatric Dose for Pyelonephritis

IR formulations: 20 mg 40 mg/kg per day orally, given every 8 to 12 hours

• Maximum dose: 1 gram/day

Duration of therapy:

• Empirical treatment: At least 48 to 72 hours after the patient becomes asymptomatic OR bacterial eradication evidence is obtained
• Acute bacterial sinusitis: 10 days
• GAS infections: At least 10 days

16 years and older:
ER tablets: 375 mg orally every 12 hours

• Maximum dose: 750 mg/day
• Duration of therapy: 7 to 10 days

Comments:

• This drug is generally effective in eradicating nasopharynx and oropharynx infections caused by S pyogenes.
• IM penicillin is the only agent shown to be effective in the prophylaxis of rheumatic fever.
• IR formulations: Doses up to 40 mg/kg may be used to treat more severe infections OR infections caused by less susceptible organisms.
• Infections caused by BLNAR H influenzae should be considered resistant to this drug.

Uses:

• Treatment of lower respiratory tract infections, including pneumonia, caused by H influenzae, S pneumoniae, and S pyogenes
• Treatment of mild to moderate uncomplicated skin and structure infections due to MSSA
• Treatment of skin and structure infections caused by S aureus and S pyogenes
• Treatment of urinary tract infections, including cystitis and pyelonephritis, caused by coagulase-negative staphylococci, E coli, Klebsiella species, and P mirabilis

Usual Pediatric Dose for Urinary Tract Infection

IR formulations: 20 mg 40 mg/kg per day orally, given every 8 to 12 hours

• Maximum dose: 1 gram/day

Duration of therapy:

• Empirical treatment: At least 48 to 72 hours after the patient becomes asymptomatic OR bacterial eradication evidence is obtained
• Acute bacterial sinusitis: 10 days
• GAS infections: At least 10 days

16 years and older:
ER tablets: 375 mg orally every 12 hours

• Maximum dose: 750 mg/day
• Duration of therapy: 7 to 10 days

Comments:

• This drug is generally effective in eradicating nasopharynx and oropharynx infections caused by S pyogenes.
• IM penicillin is the only agent shown to be effective in the prophylaxis of rheumatic fever.
• IR formulations: Doses up to 40 mg/kg may be used to treat more severe infections OR infections caused by less susceptible organisms.
• Infections caused by BLNAR H influenzae should be considered resistant to this drug.

Uses:

• Treatment of lower respiratory tract infections, including pneumonia, caused by H influenzae, S pneumoniae, and S pyogenes
• Treatment of mild to moderate uncomplicated skin and structure infections due to MSSA
• Treatment of skin and structure infections caused by S aureus and S pyogenes
• Treatment of urinary tract infections, including cystitis and pyelonephritis, caused by coagulase-negative staphylococci, E coli, Klebsiella species, and P mirabilis

Usual Pediatric Dose for Skin and Structure Infection

IR formulations: 20 mg 40 mg/kg per day orally, given every 8 to 12 hours

• Maximum dose: 1 gram/day

Duration of therapy:

• Empirical treatment: At least 48 to 72 hours after the patient becomes asymptomatic OR bacterial eradication evidence is obtained
• Acute bacterial sinusitis: 10 days
• GAS infections: At least 10 days

16 years and older:
ER tablets: 375 mg orally every 12 hours

• Maximum dose: 750 mg/day
• Duration of therapy: 7 to 10 days

Comments:

• This drug is generally effective in eradicating nasopharynx and oropharynx infections caused by S pyogenes.
• IM penicillin is the only agent shown to be effective in the prophylaxis of rheumatic fever.
• IR formulations: Doses up to 40 mg/kg may be used to treat more severe infections OR infections caused by less susceptible organisms.
• Infections caused by BLNAR H influenzae should be considered resistant to this drug.

Uses:

• Treatment of lower respiratory tract infections, including pneumonia, caused by H influenzae, S pneumoniae, and S pyogenes
• Treatment of mild to moderate uncomplicated skin and structure infections due to MSSA
• Treatment of skin and structure infections caused by S aureus and S pyogenes
• Treatment of urinary tract infections, including cystitis and pyelonephritis, caused by coagulase-negative staphylococci, E coli, Klebsiella species, and P mirabilis

Usual Pediatric Dose for Bronchitis

Children 1 month and older:
IR formulations: 20 mg 40 mg/kg per day orally, given every 8 to 12 hours

• Maximum dose: 1 gram/day

Duration of therapy:

• Empirical treatment: At least 48 to 72 hours after the patient becomes asymptomatic OR bacterial eradication evidence is obtained
• Acute bacterial sinusitis: 10 days
• GAS infections: At least 10 days

16 years and older:
ER tablets: 500 mg orally every 12 hours

• Maximum dose: 1000 mg/day
• Duration of therapy: 7 days

IR formulations: Doses up to 40 mg/kg may be used to treat more severe infections OR infections caused by less susceptible organisms.

• ER tablets given 500 mg orally 2 times a day are only clinically equivalent to immediate-release capsule formulations given 250 mg orally 3 times a day.
• Infections caused by BLNAR H influenzae should be considered resistant to this drug.

Uses:

• Treatment of mild to moderate acute bacterial exacerbations of chronic bronchitis due to H influenzae (only non-beta-lactamase-producing strains), M catarrhalis (including beta-lactamase-producing strains), or S pneumoniae
• Treatment of mild to moderate secondary bacterial infection of acute bronchitis due to H influenzae (only non-beta-lactamase-producing strains), M catarrhalis (including beta-lactamase strains), or S pneumoniae

Usual Pediatric Dose for Bacterial Infection

American Academy of Pediatrics (AAP) Recommendations:
Patients beyond the newborn period:
20 to 40 mg/kg per day, given in divided doses 2 to 3 times a day

• Maximum dose: 1 gram/day

Use: Treatment of bacterial infections

Renal Dose Adjustments

No adjustment recommended.

Liver Dose Adjustments

Data not available

Precautions

CONTRAINDICATIONS:

• Hypersensitivity to the active component, other cephalosporins, or to any of the ingredients

Safety and efficacy of capsules and oral suspensions have not been established in patients younger than 1 month.
Safety and efficacy of ER tablets have not been established in patients younger than 16 years.

Consult WARNINGS section for additional precautions.

Dialysis

Data not available

Other Comments

Administration advice:

• Many experts recommend that patients should take extended/modified release tablets with food/meals (or at least within 1 hour of eating).
• Capsules and tablets should not be chewed, crushed, or cut.
• Oral suspensions should be shaken prior to administration.

Storage requirements:

• Protect from light.
• The manufacturer product information should be consulted.

Reconstitution/preparation techniques:

• Oral suspension: The manufacturer product information should be consulted.

General:

• Local epidemiological and susceptibility patterns should be used to guide treatment selection in the absence of patient-specific culture and susceptibility information.

Patient advice:

• Advise patients to speak to their healthcare provider if they become pregnant, intend to become pregnant, or are breastfeeding.
• Patients should be directed to take the full course of treatment, even if they feel better.
• Patients should be instructed to report signs/symptoms of Clostridium difficile (e.g., watery/bloody stools, stomach cramps, fever), for up to 2 months after stopping treatment.

See also:

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

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