Hi, Congratulations on quitting smoking! It s normal for your body to go through some changes as it readjusts to life without cigarettes. One of the side effects you may be experiencing is an increase in malodorous gas. Smoking can affect gut bacteria, and quitting smoking can lead to changes in the microbiome of your gut. These changes can cause an increase in gas production and changes in the composition of the gas itself, which can result in a foul odor. There are a few things you can do to help manage the symptoms while your body adjusts: * Increase your fiber intake: Eating more fiber can help to regulate bowel movements and reduce gas. Try incorporating more fruits, vegetables, and whole grains into your diet. * Stay hydrated: Drinking plenty of water can also help to regulate bowel movements and reduce gas. * Consider probiotics: Probiotics can help to promote the growth of healthy gut bacteria and reduce symptoms of digestive discomfort. Talk to your doctor about whether probiotics may be right for you. * Avoid foods that cause gas: Certain foods are known to cause gas, including beans, broccoli, cabbage, and onions. Try avoiding these foods until your symptoms improve. * Take over-the-counter gas remedies: Over-the-counter medications, such as simethicone, can help to reduce gas and bloating. It s also important to note that if your symptoms persist or worsen, you should consult with your healthcare provider. Given that you have collagenous colitis, it may be particularly important to work with your healthcare provider to manage any gastrointestinal symptoms that you experience. Take care. Hope I have answered your question. Let me know if I can assist you further. Regards, Dr. Priyanka, General & Family Physician