This document provides dosing guidelines for various antibiotics used to treat common paediatric infections. It lists the antibiotic, type of infection treated, recommended dose based on age and weight, administration method, and treatment duration. Notable antibiotics included are amoxicillin, cefaclor, cefotaxime, ceftriaxone, co-amoxiclav, flucloxacillin and metronidazole. The dosing guidelines are intended for common bacterial infections excluding those requiring separate protocols such as cystic fibrosis, tuberculosis or oncology patients.

1. SC(NHS)FT Reg. I.D. No. 1246  Medical Guidelines for Paediatric Medicine
ANTIBIOTIC DOSES
This guidance does not cover the treatment of line infections, haematology / oncology patients, patients with Tuberculosis,
or patients with Cystic Fibrosis - please refer to separate guidelines.
SC(NHS)FT Implemented March 2018, Review March 2021 (do not use after this date) Page 1 of 10 f
2.4 ANTIBIOTIC DOSES
Antibiotic Type of infection Dose
Method of
administration Length of treatment Comments
Amoxicillin
Neonatal meningitis
Age 0-3 months
< 7 days 100mg/kg 12 hourly
7-28 days 100mg/kg 8 hourly
>1 month 100mg/kg 6 hourly
Slow IV infusion
over 30 minutes 21 days
Avail. oral preparations:
250mg capsules
125mg in 5ml
suspension
250mg in 5ml
suspension
Mild Pneumonia
Otitis media
Sinusitis
Cellulitis
Dental abscess
1 month – 1 year 125mg three times a day
1- 5 years 250mg three times a day
5-18 years 500mg three times a day
Oral Otitis media : 5-7 days
Sinusitis: 7 days
Dental abscess: 7
days
Benzylpenicillin Severe cellulitis
Pneumonia
Age < 7days 50mg/kg twice day
7 – 28 days 50mg/kg three times a day
1 month - 18 years 50mg/kg four times
daily
Slow IV over 30
minutes
Depends on clinical
response Age 1 month – 18
years:
Max 2.4g four times
daily
Cefaclor Bacterial chest
infection
Age 1month - 1 year 62.5mg three times a
day
Age 1 - 5 years 125mg three times a day
Age > 5 years 250 mg three times a day
Oral
Doses may be doubled
in infections caused by
less susceptible
organisms
Avail. oral preparations:
250mg & 500mg
capsules
125mg in 5 ml
suspension
250mg in 5 ml
suspension

2. SC(NHS)FT Reg. I.D. No. 1246  Medical Guidelines for Paediatric Medicine
ANTIBIOTIC DOSES
This guidance does not cover the treatment of line infections, haematology / oncology patients, patients with Tuberculosis,
or patients with Cystic Fibrosis - please refer to separate guidelines.
SC(NHS)FT Implemented March 2018, Review March 2021 (do not use after this date) Page 2 of 10 f
Antibiotic Type of infection Dose
Method of
administration Length of treatment Comments
Cefalexin UTI
< 7days 25mg/kg (max 125mg) twice daily
7-21days 25mg/kg(max 125mg) three times
a day
21-28days 25mg/kg (max 125mg) four
times a day
1 mth – 12 yrs 25mg/kg twice daily (Max
1g)
OR
1 month –1 year 125mg twice daily
1-5 years 125mg -250mg three times a
day
6-12 years 250mg-500mg three times a
day
12-18 years 500mg twice daily
Oral 7 days Avail. oral preparations:
250mg & 500mg tablets
125mg in 5 ml
suspension
250mg in 5 ml
suspension
Cefotaxime Neonatal meningitis,
osteomyelitis & sepsis
Age < 7 days 50 mg/kg twice daily
7-21 days 50mg/kg three times daily
> 21 days 50mg/kg three to four
times a day
Slow IV bolus
Refer to Bacterial
Meningitis Guideline in
Medical Guidelines
Maximum adult daily
dose 12g
Emergency treatment:
Initial dose of 100mg/kg
(max dose 2g) may be
given as a short infusion
Meningitis
Acute Epiglottitis
Meningococcal sepsis
Osteomyelitis
Age > 1 month 50mg/kg four times
daily
NB: osteomyelitis >3
months, see cefuroxime
Ceftriaxone
Meningitis
Meningococcal
sepsis
Acute epiglottitis
Birth -to 15 day 50mg/kg once daily
Age > 15 days - 11 years (body weight up
to 50kg) 80mg/kg
>50kgs or 12-17 years: 4g once daily
IV infusion over
60 minutes in
neonates
IV infusion over
at least
30minutes if > 1
month of age
Refer to Bacterial
Meningitis Guideline in
Medical Guidelines
Max. daily dose 4g
Please note IM
Ceftriaxone is not
recommended to
complete the course

3. SC(NHS)FT Reg. I.D. No. 1246  Medical Guidelines for Paediatric Medicine
ANTIBIOTIC DOSES
This guidance does not cover the treatment of line infections, haematology / oncology patients, patients with Tuberculosis,
or patients with Cystic Fibrosis - please refer to separate guidelines.
SC(NHS)FT Implemented March 2018, Review March 2021 (do not use after this date) Page 3 of 10 f
Antibiotic Type of infection Dose
Method of
administration Length of treatment Comments
Meningitis prophylaxis Adult : 250 mg single dose IM (Adult
prophylaxis only)
Prophylaxis in pregnant
contacts
Cefuroxime UTI
Peritonitis
Pneumonia
Orbital &
periorbital cellulitis
Osteomyelitis & septic
arthritis (Age >3
months)
Age < 7days 30 mg/kg twice daily
Age 7 - 20 days 30 mg/kg three times
daily
Age 21-28 days 30 mg/kg four times a day
Age > 1 month 30 mg/kg three times
daily
Do not exceed adult dose (1.5g three times
a day)
Slow IV bolus
Consider 50mg/kg in
osteomyelitis, septic
arthritis, severe
pneumonia and other
severe infections.
Chloramphenicol Bacterial conjunctivitis 1 drop / application of ointment
4 - 6 times a day
Topical Continue for 48 hours
after eyes clear
Available preparations:
0.5% eye drops
1% eye ointment
Ciprofloxacin
Meningococcal
prophylaxis
1month – 5 years : 125mg single dose
Children 5-12 years (only if able to swallow
tablets): 250mg single dose
Adults and children >12 yrs:
500mg single dose
Oral Single dose
Ciprofloxacin 250mg
tabs.
250mg in 5ml
Suspension
NB suspension not
normally dispensed for
meningitis prophylaxis.
Please see Rifampicin if
liquid preparation
needed for prophylaxis
Shigella & Salmonella Neonate 15mg/kg twice daily
1 month – 18 years 20mg/kg (max 750mg)
twice daily
Oral 7 days
Severe animal &
human bites in
patients allergic to
penicillin
Neonate 15mg/kg twice daily
1 month – 18 years 20mg/kg (max 750mg)
twice daily
Oral 10 – 14 days

4. SC(NHS)FT Reg. I.D. No. 1246  Medical Guidelines for Paediatric Medicine
ANTIBIOTIC DOSES
This guidance does not cover the treatment of line infections, haematology / oncology patients, patients with Tuberculosis,
or patients with Cystic Fibrosis - please refer to separate guidelines.
SC(NHS)FT Implemented March 2018, Review March 2021 (do not use after this date) Page 4 of 10 f
Antibiotic Type of infection Dose
Method of
administration Length of treatment Comments
Clarithromycin Pneumonia
URTI
Campylobacter
enteritis
Skin infections
Chlamydial
conjunctivitis
Intravenous infusion
1 month – 12 years 7.5mg/kg (max 500mg)
twice daily
12-18 years 500mg twice a day
Oral
<8kg 7.5mg/kg twice daily
8-11kg 62.5mg twice daily
12-19kg 125mg twice daily
20-29kg 187.5mg twice daily
30-40kg 250mg twice daily
12-18 years 500mg twice daily
IV infusion over
60 mins
Oral
Pertussis 7 days
Pneumonia (atypical)
7 days
Skin infections 7-14
days
Chlamydial
conjunctivitis: 14days
Consider switch to oral
preparation as soon as
enteral absorption is
satisfactory
Avail. oral preparations:
250mg & 500mg tablets
125mg in 5ml
suspension
250mg in 5 ml
suspension
Clindamycin Compound fractures
Severe human/animal
bites (in combination)
in patients allergic to
penicillin
Enteral dose:
<14 days 3-6mg/kg three times a day
14 – 28 days 3-6 mg/kg four times a day
1 mth – 18 yrs 3-6 mg/kg (max 450mg)
four times a day
IV dose:
1 mth – 18 yrs: 3.75-6.25mg/kg four times
a day
Oral
IV infusion over
10 - 60 minutes
Avail. oral preparations:
75mg & 150mg
capsules
75mg/5ml liquid
Maximum IV dose:
10mg/kg four times a
day (4.8g daily)

5. SC(NHS)FT Reg. I.D. No. 1246  Medical Guidelines for Paediatric Medicine
ANTIBIOTIC DOSES
This guidance does not cover the treatment of line infections, haematology / oncology patients, patients with Tuberculosis,
or patients with Cystic Fibrosis - please refer to separate guidelines.
SC(NHS)FT Implemented March 2018, Review March 2021 (do not use after this date) Page 5 of 10 f
Antibiotic Type of infection Dose
Method of
administration Length of treatment Comments
Co-amoxiclav Human & animal
bites
Peritonitis (oral switch)
Peri-orbital / Orbital
cellulitis
Bacterial chest
infection
Pneumonia
Compound fractures
Skin infections
Osteomyelitis & septic
arthritis (oral switch)
Birth -1 year 0.25ml/kg of the 125/31
suspension three times daily
1-6 years 5ml of the 125/31
suspension
three times daily
7-12 years 5ml of the 250/62
suspension
three times daily
13-18 years 1 tablet (500/125) or 10ml
of the 250mg/62 suspension three times
daily
Birth – 3months 30mg/kg every 12 hours
3 month- 18 years 30mg/kg (max 1.2g)
every eight hours
Oral
Slow IV bolus
Human & animal bites:
Prophylaxis 3 days
Treatment 10-14 days
Other conditions:
Length of treatment
depends on clinical
condition
Avail. oral preparations:
Co-amoxiclav syrup
125/31mg in 5 ml syrup
250/62 mg in 5 ml syrup
Co-amoxiclav
250/125mg &
500/125mg tablets
Co-amoxiclav IV
preparations:
600mg and 1.2g.
(Dosage based on co-
amoxiclav content)
Co-trimoxazole
Human/
animal bites (recent
and no signs of
infection) in patients
allergic to penicillin
6 weeks – 6months 120mg twice a
day
6months – 6 years 240mg twice a
day
6-12 years 480 mg twice a
day
12-18 years 960mg twice a
day
Oral Prophylaxis for
3 days
Avail. Oral preparations:
240mg/5ml liquid
480mg/5ml liquid
480mg & 960mg tablets

6. SC(NHS)FT Reg. I.D. No. 1246  Medical Guidelines for Paediatric Medicine
ANTIBIOTIC DOSES
This guidance does not cover the treatment of line infections, haematology / oncology patients, patients with Tuberculosis,
or patients with Cystic Fibrosis - please refer to separate guidelines.
SC(NHS)FT Implemented March 2018, Review March 2021 (do not use after this date) Page 6 of 10 f
Antibiotic Type of infection Dose
Method of
administration Length of treatment Comments
Flucloxacillin Skin infections Age <7 days 25-50mg/kg twice a
day
Age 8–21 days 25-50mg/kg three times
daily
22 - 28 days 25-50mg/kg four times a
day
Age 1 month-18 years 25- 50mg/kg (max
1g) four times a day
Age < 7 days 25mg/kg twice a day
Age 8-21 days 25mg /kg three times a
day
22-28 days 25mg/kg four times daily
1 month- 2 years
62.5mg-125mg four times daily
2-10 years
125mg-250mg four times daily
> 10 years
250mg-500mg four times daily
Slow IV bolus
Oral
NB Adult IV dose up to
2g four times daily
Adult oral dose 500mg
four times a day
Avail. oral preparations:
Flucloxacillin syrup
125mg in 5 ml
suspension
250mg in 5 ml
suspension
250mg & 500mg
capsules
Fusidic acid
Bacterial
conjunctivitis
If recommended by
Microbiologist (& in
combination with
second antibiotic
agent)
1 drop in affected eye twice daily
< 1 month 15mg/kg three times a day
1 month - 1year 15mg/kg three times a
day
1year-5 years 250mg three times a day
5-12 years 500mg three times daily
12-18 years: 750mg three times a day
fusidic acid or 500mg
Topical
Oral
Continue for 48
hours after eyes clear
Prolonged treatment
required
Fusidic acid 1% eye
drops
Avail. oral preparations:
250mg in 5 ml fusidic
acid suspension
250 mg sodium fusidate
tablets
(500mg sodium fusidate
is equivalent to 750mg
fusidic acid)

7. SC(NHS)FT Reg. I.D. No. 1246  Medical Guidelines for Paediatric Medicine
ANTIBIOTIC DOSES
This guidance does not cover the treatment of line infections, haematology / oncology patients, patients with Tuberculosis,
or patients with Cystic Fibrosis - please refer to separate guidelines.
SC(NHS)FT Implemented March 2018, Review March 2021 (do not use after this date) Page 7 of 10 f
Antibiotic Type of infection Dose
Method of
administration Length of treatment Comments
Gentamicin
Serious Gram
negative infections
“Guidelines for Once Daily Gentamicin in
Infants & Children” available on SC(NHS)T
Intranet site – ‘Trust Approved Guidelines’
and the Laboratory Handbook page 63
Meropenem Serious aerobic and
anaerobic Gram
positive gram positive
and Gram negative
infections.
Infections caused by
Extended Spectrum
Beta Lactamase
(ESBL) producing
bacteria
Birth to 7 days 20 mg/kg every 12 hours
7 – 28 days 20 mg/kg every 8 hours
1month- 12 years and under 50kg
20 mg/kg every 8 hours
12-18 years or over 50kg
1g every 8 hours
IV bolus
(40mg/kg & 2g
doses should be
given by IV
infusion)
Dose doubled where
meningitis cover is
required
Metronidazole
Peritonitis
Peri-orbital or
Orbital cellulitis
Clostridium
difficile diarrhoea
Dental abscess
Birth (>34 weeks) – 2 months
7.5mg/kg three times a daily
2 months - 18 years 7.5mg/kg (max
500mg) three times daily
1 month – 2months 7.5mg/kg twice a day
2 mth – 12 yrs 7.5mg/kg (max 400mg) three
times a day
12 – 18 years
400mg three times a day
or in dental infections
1-3 years 50 mg three times a day
3-7 years 100mg twice a day
7-10 years 100 mg three times a day
10-18 years 200mg three times a day
IV infusion over
20-30 minutes
Oral C.difficile : 14days
Dental infection : 7
days
Maximum IV dose
500mg
Maximum oral dose
400mg
Metronidazole :Avail.
oral preparations:
200mg tablets
200mg in 5 ml
suspension

8. SC(NHS)FT Reg. I.D. No. 1246  Medical Guidelines for Paediatric Medicine
ANTIBIOTIC DOSES
This guidance does not cover the treatment of line infections, haematology / oncology patients, patients with Tuberculosis,
or patients with Cystic Fibrosis - please refer to separate guidelines.
SC(NHS)FT Implemented March 2018, Review March 2021 (do not use after this date) Page 8 of 10 f
Antibiotic Type of infection Dose
Method of
administration Length of treatment Comments
Nitrofurantoin UTI
TREATMENT:
>3 mths – 12 yrs 750 microgram/kg four
times a day
12 – 18 years 50mg four times daily
PROPHYLAXIS:
Age > 3 months 1mg/kg at night
12 18 years 50-100mg at night
Oral
Oral
7 days
Adult dose 50mg
four times daily
Avail. oral preparations:
Nitrofurantoin 50mg
tablet
Nitrofurantoin
suspension 25mg in 5
ml suspension
Penicillin V Tonsillitis Age 1 month - 1 year 62.5mg four times
daily
1-5years 125mg four times daily
6-12 years 250mg four times daily
> 12 years 500mg four times daily
Oral Tonsillitis: 10 days
Please note: not
suitable for treatment
of streptococcal
infection in any other
body sites
Avail. oral preparations:
Severe infection may
require IV therapy
Penicillin V syrup
125mg in 5 ml syrup
250mg in 5 ml syrup
Penicllin V tabs 250mg
tablets
Rifampicin Meningitis
Prophylaxis:
- Contacts
- Nasal eradication in
index case, :
Meningococcal and
nasal
eradication in index
case
Birth- 1 year 5mg/kg twice a day
> 1 year 10mg/kg twice a day
or 1-2 years 100mg twice a day
3-4 years 150mg twice a day
5-6 years 200mg twice a day
7-12 years 300mg twice a day
Adults and children > 12 years 600mg
twice daily
Oral Meningococcus:
2 days
Rifampicin can colour
body fluids orange/red
Avoid with soft contact
lenses
NB: Numerous drug
interactions. Check
BNFc
Avail. oral preparations:
Rifampicin syrup
100mg in 5 ml syrup
Rifampicin 150mg &
300mg capsules
Severe staphylococcal
infection
Osteomyelitis
Septic arthritis
Age 1month - 18 years 10mg/kg (max
600mg) twice a day
Oral Prolonged therapy
required
In combination with
second antibiotic agent

9. SC(NHS)FT Reg. I.D. No. 1246  Medical Guidelines for Paediatric Medicine
ANTIBIOTIC DOSES
This guidance does not cover the treatment of line infections, haematology / oncology patients, patients with Tuberculosis,
or patients with Cystic Fibrosis - please refer to separate guidelines.
SC(NHS)FT Implemented March 2018, Review March 2021 (do not use after this date) Page 9 of 10 f
Antibiotic Type of infection Dose
Method of
administration Length of treatment Comments
Teicoplanin Severe staphylococcal
infection
1month – 18years
10mg/kg (max 400mg) every 12 hours for 3
doses then either
10mg/kg (max 400mg) once daily for line
infections, neutropenia, or severe
infections
OR
6mg/kg once daily (max 400mg)
IV Requires use of Baxa
filters (green -5 micron)
and Braun lubricant free
syringes (green)
available from
pharmacy
Antibiotic levels required
if used for invasive
Staph aureus infection –
discuss with
Microbiology
Trimethoprim UTI TREATMENT:
Birth – 1 month
Initially 3mg/kg single dose followed by
2mg/kg twice daily
1 month -12 yrs 4mg/kg (max 200mg)
twice daily
12 – 18 years 200mg twice daily
PROPHYLAXIS:
Birth-1 month 2mg/kg at night
1 mth – 12 yrs 2mg/kg at night
(max 100mg)
12 – 18 years 100mg at night
Oral 7 days Avail. oral preparations:
Trimethoprim
100mg & 200mg tablets
50mg in 5ml suspension
Vancomycin Clostridium difficile
Diarrhoea
Consult Microbiologist
1 month - 5 years 5mg/kg four times a day
5-12 years 62.5mg four times a day
12-18 years 125mg four times a day
Oral 14 days Not significantly
absorbed
Avail. oral preparations:
125mg capsules
Injection can be given
orally

10. SC(NHS)FT Reg. I.D. No. 1246  Medical Guidelines for Paediatric Medicine
ANTIBIOTIC DOSES
This guidance does not cover the treatment of line infections, haematology / oncology patients, patients with Tuberculosis,
or patients with Cystic Fibrosis - please refer to separate guidelines.
SC(NHS)FT Implemented March 2018, Review March 2021 (do not use after this date) Page 10 of 10 f
Antibiotic Type of infection Dose
Method of
administration Length of treatment Comments
Vancomycin
Serious Gram positive
infections
1month – 18 years
15mg/kg every 8 hours adjusted
according to vancomycin concentration
IV infusion 14 days Follow dilution
guidelines and give over
at least an hour.
Regular vancomycin
concentration
monitoring required.
Trough before 4th dose
(in 8 hourly dosing).
Target trough level is
10-15mg/L in most
circumstances – discuss
with Microbiology if
further advice required.
(Updated by Gill Hinson, April 2018)
(Section 2.4 updated by Dr S Thompson & Rachel Phillips, April 2015)
(Section 2.4 reviewed by Dr P Fenton, April 2013)