Microbiome Test Sample Collection Guide

Simple answers to common questions

Find answers to the questions we hear most often. From our technology and products to accreditation, partnerships and the future of Microba.

How long should I wait to collect my sample after finishing antibiotics?

Ideally wait at least one month after finishing antibiotics or antimicrobials before collecting a sample. After a short course of broad-spectrum antibiotics — five to 10 days — most gut microbial species return to baseline within one to two months.

Some changes can persist for a year or more, and there's limited data on prolonged antibiotic use, where recovery is likely to take longer. One study showed recovery only after nine months following three months of amoxicillin.

So the one-month minimum is what we advise based on current research, with the understanding that full recovery may take longer in some cases.

How much time should a patient allow to take the test?

We recommend collecting from your first bowel movement of the day, as this gives the most accurate result. Allow yourself around 45 minutes for the whole process — that way you can take your time, follow each step, and complete the sampling without rushing.

I'm having trouble taking my sample in the morning — can I take it in the afternoon?

Yes, if you live in a metropolitan area, you can collect your sample in the afternoon or evening. Here's what to do — collect on Sunday or Monday afternoon or evening, and record the date and time on the labels.

Follow the instructions in your booklet, then post the package on Monday or Tuesday morning at the post office counter — not in a street post box.

This approach isn't suitable for regional or rural clients, because longer transit times put the sample outside its stability window.

Is the sample contaminated if it comes into contact with toilet paper?

A small piece of toilet paper in the sample doesn't make it invalid. The sample can still be processed, and the results remain reliable.

Is it possible to collect a sample from a colostomy bag?

Yes — a sample can be transferred from the colostomy bag into the pottle, just as you would emptying it into the toilet. That works perfectly well for processing the sample for microbiome analysis.

What impact do enemas have on Microbiome Explorer test results?

Enemas can affect both GI markers and the gut microbiome, so we recommend avoiding them before stool collection where possible — particularly when testing for faecal elastase. If an enema has been used, wait at least 24 to 48 hours before collecting a sample.

Why does this matter? Enemas can alter stool pH and elastase results, and surfactant or soap-based enemas may also affect the stability of other biomarkers. A short delay gives you a much cleaner picture.

Can you guarantee sample stability for international shipping?

Yes — we've tested and validated sample stability for international transit. We use monitored, temperature-controlled shipping with specialist providers who are trained to our specific requirements. That ensures samples arrive at our laboratories without compromising the analytes we're measuring.

Why do samples need to reach the UK lab within 72 hours of collection?

It's about biomarker stability. GI health markers are sensitive to time and temperature, so the 72-hour window is what we've validated to keep the analytes stable and your results accurate. We've tested these markers extensively under our specific return shipping conditions — using an ice block and insulated pouch — and 72 hours is where the data confidently sits.

Can samples be sent from the Channel Islands, including Guernsey and Jersey?

Not at the moment. Microbiome Explorer isn't currently available in Guernsey or Jersey because samples need to reach our UK lab within 72 hours, and current logistics from the Channel Islands don't reliably support that. We are looking at ways to extend the stability period in future, so this may change.

Why does the sample need to be posted before 1pm Monday to Wednesday?

It comes down to two things — operating hours and sample stability. Samples need to start processing within 72 hours of collection, and our lab operates Monday to Friday, 8.30am to 5pm. Posting before 1pm Monday to Wednesday gives the postal service enough time to deliver within those hours and within that 72-hour window.

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Simple answers to common questions