Your gut microbiome is a vast collection of microbes, including bacteria, that exist in your digestive tract, which can be affected by the process required to prepare for a colonoscopy, which often includes a period of fasting, consumption of a liquid laxative, and use of an enema. Through this process, your microbiome is altered, although it often returns to its prior form within a month, as an adult microbiome is a stable area that will tend to only experience short-term changes associated with colonoscopy preparation, illness, or ingestion of foods that vary from your regular diet. Based on current knowledge, modern colonoscopy preparation steps don’t affect the microbiome for more than a short period of time, and research into the long-term effects of these preparation methods also continues to be ongoing.