Formulary
Cefaclor: Indications, Dosing, Side Effects and Interactions
Cephalosporins are antibacterials that attach to penicillin binding proteins to interrupt cell wall biosynthesis, leading to bacterial cell lysis and death.
MedNext Academy | 5 min read
Cefaclor: Indications, Dosing, Side Effects and Interactions
Cephalosporins are antibacterials that attach to penicillin binding proteins to interrupt cell wall biosynthesis, leading to bacterial cell lysis and death.
Drug action
Cephalosporins are antibacterials that attach to penicillin binding proteins to interrupt cell wall biosynthesis, leading to bacterial cell lysis and death.
Indications and dose
**Susceptible infections due to sensitive Gram-positive and Gram-negative bacteria**
- **Child** (By Mouth Using Immediate-Release Medicines): 12-17 years 250 mg 3 times a day; maximum 4 g per day.
- **Adult** (By Mouth Using Immediate-Release Medicines): 250 mg 3 times a day; maximum 4 g per day.
- **Child** (By Mouth Using Modified-Release Medicines): 12-17 years 375 mg every 12 hours, dose to be taken with food.
- **Adult** (By Mouth Using Modified-Release Medicines): 375 mg every 12 hours, dose to be taken with food.
**Severe susceptible infections due to sensitive Gram-positive and Gram-negative bacteria**
- **Child** (By Mouth Using Immediate-Release Medicines): 12-17 years 500 mg 3 times a day; maximum 4 g per day.
- **Adult** (By Mouth Using Immediate-Release Medicines): 500 mg 3 times a day; maximum 4 g per day.
**Pneumonia**
- **Child** (By Mouth Using Modified-Release Medicines): 12-17 years 750 mg every 12 hours, dose to be taken with food.
- **Adult** (By Mouth Using Modified-Release Medicines): 750 mg every 12 hours, dose to be taken with food.
**Lower urinary-tract infections**
- **Child** (By Mouth Using Modified-Release Medicines): 12-17 years 375 mg every 12 hours, dose to be taken with food.
- **Adult** (By Mouth Using Modified-Release Medicines): 375 mg every 12 hours, dose to be taken with food.
**Asymptomatic carriage ofHaemophilus influenzaeor mild exacerbations in cystic fibrosis**
- **Child** (By Mouth Using Immediate-Release Medicines): 7-17 years 500 mg 3 times a day.
**Susceptible infections due to sensitive Gram-positive and Gram-negative bacteria for cefaclor**
- **Child 1-11 months** (By mouth using immediate-release medicines): 20 mg/kg daily in 3 divided doses, alternatively 62.5 mg 3 times a day.
- **Child 1-4 years** (By mouth using immediate-release medicines): 20 mg/kg daily in 3 divided doses, alternatively 125 mg 3 times a day.
- **Child 5-11 years** (By mouth using immediate-release medicines): 20 mg/kg daily in 3 divided doses, usual max. 1 g daily, alternatively 250 mg 3 times a day.
- **Child 12-17 years** (By mouth using immediate-release medicines): 250 mg 3 times a day; maximum 4 g per day.
- **Child 12-17 years** (By mouth using modified-release medicines): 375 mg every 12 hours, dose to be taken with food.
**Severe susceptible infections due to sensitive Gram-positive and Gram-negative bacteria for cefaclor**
- **Child 1-11 months** (By mouth using immediate-release medicines): 40 mg/kg daily in 3 divided doses, usual max. 1 g daily, alternatively 125 mg 3 times a day.
- **Child 1-4 years** (By mouth using immediate-release medicines): 40 mg/kg daily in 3 divided doses, usual max. 1 g daily, alternatively 250 mg 3 times a day.
- **Child 5-11 years** (By mouth using immediate-release medicines): 40 mg/kg daily in 3 divided doses, usual max. 1 g daily.
- **Child 12-17 years** (By mouth using immediate-release medicines): 500 mg 3 times a day; maximum 4 g per day.
**Pneumonia for cefaclor**
- **Child 12-17 years** (By mouth using modified-release medicines): 750 mg every 12 hours, dose to be taken with food.
**Lower urinary-tract infections for cefaclor**
- **Child 12-17 years** (By mouth using modified-release medicines): 375 mg every 12 hours, dose to be taken with food.
**Asymptomatic carriage of Haemophilus influenzae or mild exacerbations in cystic fibrosis for cefaclor**
- **Child 1-11 months** (By mouth using immediate-release medicines): 125 mg every 8 hours.
- **Child 1-6 years** (By mouth using immediate-release medicines): 250 mg 3 times a day.
- **Child 7-17 years** (By mouth using immediate-release medicines): 500 mg 3 times a day.
Side effects
Common or very common Abdominal pain; diarrhoea; dizziness; eosinophilia; headache; leucopenia; nausea; neutropenia; pseudomembranous enterocolitis; skin reactions; thrombocytopenia; vomiting Uncommon Anaphylactic reaction; angioedema Rare or very rare Agranulocytosis; haemolytic anaemia; nephritis tubulointerstitial (reversible); severe cutaneous adverse reactions (SCARs) Side-effects For cefaclor Frequency not known Akathisia; anxiety; aplastic anaemia; arthralgia; arthritis; asthenia; colitis; confusion; drowsiness; dyspnoea; fever; genital pruritus; hallucination; hepatitis (transient); hypersensitivity; increased risk of infection; insomnia; jaundice cholestatic (transient); lymphadenopathy; lymphocytosis; muscle tone increased; oedema; paraesthesia; proteinuria; syncope; vasodilation Side-effects, further information Cefaclor is associated with protracted skin reactions, especially in children.
Interactions
**Other interactions (7):**
- Effect on organic anion transporter 3 (OAT3) substrates There was an increase in mean cefaclor C max and AUC (1.43- and 1.54-fold, respectively), following repeated doses of A771726, suggesting that...
- Therefore, when co-administered with substrates of OAT3, such as cefaclor, benzylpenicillin, ciprofloxacin, indomethacin, ketoprofen, furosemide, cimetidine, methotrexate, zidovudine, caution is...
- OAT3 substrates Concomitant administration of cenobamate and medicinal products transported by OAT3 may result in higher exposure of these medicinal products.
- Effect of teriflunomide on organic anion transporter 3 (OAT3) substrates There was an increase in mean cefaclor Cmax and AUC (1.43- and 1.54-fold, respectively), following repeated doses of...
- Therefore, when teriflunomide is coadministered with substrates of OAT3, such as cefaclor, benzylpenicillin, ciprofloxacin, indometacin, ketoprofen, furosemide, cimetidine, methotrexate, zidovudine,...
- Magnesium salts may interfere with the absorption of many drugs including (but not limited to) ACE inhibitors (captopril, enalapril, fosinopril); antibacterials and antifungals (azithromycin,...
Pregnancy
Not known to be harmful.
Breast feeding
Present in milk in low concentration, but appropriate to use.
Renal impairment
Use with caution. M
Medicinal forms
Tablet,Capsule,Suspension
Clinical governance
**Author:** MedNext Clinical Team. **Clinical reviewer:** Dr Shameer Deen, MBBS, MS, MRCS. **Sources:** BNF, Indian Pharmacopoeia, CIMS India. **Correction:** Report errors at support@mednext.academy.
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