Condition category
Infections and Infestations
Date applied
Date assigned
Last edited
Retrospectively registered
Overall trial status
Recruitment status
No longer recruiting

Plain English Summary

Background and study aims
The human gut has been identified as one of the parts of the body that is most densely populated with bacteria (known collectively as the gut microbiota). Antibiotics are used to combat infections caused by harmful (pathogenic) bacteria. However, antibiotics can have a damaging effect on the gut microbiota and can lead to the development of bacteria that are resistant to antibiotics. Probiotics are live bacteria and yeasts that may be good for your health. This study will assess the effects of taking probiotics when taking antibiotics on the composition of the gut microbiota and whether there are any changes in the incidence of antibiotic-resistant organisms.

Who can participate?
Children aged 3-18 years with infections requiring antibiotic treatment.

What does the study involve?
Participants will be randomly allocated to take either probiotics or placebo (dummy) tablets for 30 days and provide stool, urine and saliva samples at the start of the study, upon completion of the antibiotic course and after 30 days (at the end of the study). Parents/guardians will need to complete a diet and physical activity questionnaire at the start and end of the study and also record children's weekly health diaries.

What are the possible benefits and risks of participating?
Probiotic supplementation is intended to prevent disruption of the gut microbiota. There are no known risks to participants taking part in this study.

Where is the study run from?
Children's Health Centre Juvenalia Ltd, Dunajska Streda, Slovakia.
Institute of Medical Chemistry, Comenius University, Bratislava, Slovakia.

When is the study starting and how long is it expected to run for?
From November 2014 to December 2015.

Who is funding the study?
Cultech Ltd, Port Talbot, UK.

Who is the main contact?
Associate Professor Jana Muchova.

Trial website

Contact information



Primary contact

Assoc. Prof Jana Muchova


Contact details

Institute of Medical Chemistry
Biochemistry and Clinical Biochemistry
Faculty of Medicine
Comenius University

Additional identifiers

EudraCT number number

Protocol/serial number


Study information

Scientific title

A study to Investigate the impact of probiotics on children's gut microbiota following antibiotic therapy



Study hypothesis

This study aims to investigate the impact of supplementation with Lab4 probiotics on the gut microbiota of 3 to 18 year olds when administered in conjunction with antibiotic therapy.

Ethics approval

Ethical committee of Trnava Self-Governing Region, 22/01/2015

Study design

Randomised double-blind placebo-controlled single-centre study

Primary study design


Secondary study design

Randomised controlled trial

Trial setting


Trial type


Patient information sheet

Not available in web format, please use the contact details below to request a patient information sheet


Oral antibiotic therapy


Participants randomised to active or placebo group will take study products orally once daily for 30 days:
1. The active will contain Lab4 probiotic consortium (Lactobacillus acidophilus CUL60, Lactobacillus acidophilus CUL21, Bifidobacterium bifidum CUL20 and Bifidobacterium animalis subsp. lactis CUL34) at 2.5x10^10 CFU per day
2. The placebo control will be an identical looking tablet containing maltodextrin
Both interventions will be prepared by Cultech Ltd, Port Talbot, UK

Intervention type



Drug names

Primary outcome measures

1. Changes in the composition and diversity of gut microbiota
2. Changes in metabonomic profiles. Stool and urine samples to be taken within 24 hours of first antibiotic dose, on the day of last antibiotic dose and on last day of active or placebo intervention dose at day 30

Secondary outcome measures

1. Impact of probiotics on wellbeing (changes in bowel habits, blood pressure, etc)
2. Changes in composition and diversity of oral microbiota
3. Stool and saliva samples at baseline, completion of antibiotic course and upon completion of the probiotic or placebo intervention at day 30

Overall trial start date


Overall trial end date


Reason abandoned


Participant inclusion criteria

1. Children aged 3 to 18 years old of either sex with infections requiring treatment by one of the following classes of antibiotics: cephalosporins; clarithromycin and amoxicllins/clavulanic acids
2. Participants willing to provide saliva, urine and stool samples
3. Parents/guardians willing to give written informed consent and information on children's daily bowel habits

Participant type


Age group




Target number of participants


Participant exclusion criteria

1. Participants whose parents are unable/unwilling to give written formal consent
2. Participants not prepared to provide saliva, urine and stool samples
3. Participants who took antibiotics in the 4 weeks prior to enrolment
4. Participants sensitive to xylitol or sorbitol

Recruitment start date


Recruitment end date



Countries of recruitment


Trial participating centre

Children's Health Centre Juvenalia Ltd
NsP, Velkoblahovska 23
Dunajska Streda

Sponsor information


Cultech Ltd

Sponsor details

Unit 2-3
Christchurch Road
Baglan Industrial Park
Port Talbot
SA12 7BZ
United Kingdom

Sponsor type




Funder type

Not defined

Funder name

Cultech Ltd (UK)

Alternative name(s)

Funding Body Type

Funding Body Subtype


Results and Publications

Publication and dissemination plan

To be confirmed at a later date.

Intention to publish date

Participant level data

Not expected to be available

Results - basic reporting

Publication summary

Publication citations

Additional files

Editorial Notes