Probably 90% of all colonics take about 45 minutes.  It could also be shorter or longer than that, based upon the judgement of the therapist and sometimes, the wishes of the client. 

There will also be about 15 minutes required before the colonic for the therapist to go over your medical history, another 15 minutes should be allowed for changing. 

On a first colonic you should expect to spend about an hour at the clinic.

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