Antibiotic colitis, also known as antibiotic-associated colitis, is a condition of the large intestines where the bacteria found in the colon suffer an imbalance due to the ingestion of an antibiotic. In each of us, there is a basic symmetry of bacteria, both "good" and "bad." The good bacteria keep the number of bad bacteria in check. If a disruption occurs within the quantity of good bacteria, the bad bacteria can lay claim to the body, in this case the colon. When this happens, the lining of the colon will suffer an inflammation, causing a number of uncomfortable symptoms.
With antibiotic colitis, most people suffer from disruptions in their bowel movements. The most common of these is a bout of diarrhea. When bad bacteria overpopulate the colon, a byproduct is created in the form of a toxin. This toxin causes the colon walls to become inflamed. Once inflammation takes place, it can prompt stool to move through the colon faster than normal. Usually, as the stool passes through the colon, water is leeched from it, causing it to harden to a certain degree. At this now faster rate, the process of absorption doesn't fully happen, which produces loose, watery stool. This causes a person to suffer from diarrhea and often an increased urgency of movements.
Blood & Mucus
During an episode of antibiotic colitis, it's also not uncommon for a person to notice the presence of blood or mucus in their stool. While it may be difficult for some to discern whether they have blood in their stool, there are a couple of telltale signs. The stool will appear either dark and tarry or with trace amounts of red. Mucus, on the other hand, is much easier to detect, as it will look much like the mucus from the nose.
Pain & Cramping
For many people, antibiotic colitis brings with it some pain and cramping. Everyone's colon has a natural rhythm where its muscles contract and relax. This is what helps the stool move through the large intestines. When the colon becomes inflamed, this rhythm is disrupted, prompting more and longer contractions and causing a person to suffer both pain and cramping.
For others, the overgrowth of bad bacteria--or at least the toxins they produce--will cause them to suffer from some level of nausea. Though the troubles lie within the large intestines, its effects can be felt throughout the digestive system, which can prompt people to experience periodic episodes of nausea.
Antibiotic colitis can also cause a person to suffer from a fever. This fever is usually around 101 degrees Fahrenheit or higher.
It is also possible for a person suffering from antibiotic colitis to experience some dehydration. As mentioned before, the colon leeches a certain amount of fluids from the stool during the process of digestion. But since the stool is moving at a much faster rate, the same amounts of fluid are no longer being absorbed and are actually lost during bowel movements. This can prompt dehydration is some individuals.