Brief Answer: ?Stomach infection or biliary obstruction Detailed Answer: Hi XXXX, Thanks for writing in to us. Vomiting is a mechanism in the body to expel contents usually from to stomach to the exterior through the oral cavity. Often vomiting occurs due to a stomach and bowel infection. It can also be due to bowel obstruction. Vomiting can also happen in liver and gall bladder problems. As you have had gall bladder removal surgery just a year back, possibility of an obstruction in the flow of bile is the first thing that needs to be excluded. However, if you have recently had any possible contaminated foods, and infection must be ruled out. Pus being expelled in vomit is less likely as it happens only in the severely ill and the patient has toxic symptoms like continuous high fever and pain in abdomen. At most you might be vomiting altered food particles. As it is grey in color, possibility of blood in vomit is also ruled out. It would be important to know if your are having any signs of biliary obstruction like yellowish discoloration of urine, eyes and skin or itching over your body. If present, needs to be confirmed by blood tests. I suggest you consult a doctor and get a confirmation if you have an infection or biliary obstruction. Further tests like X ray abdomen and ultrasound scan may be done if felt necessary. Meanwhile please take enough fresh fluids and juices. Take small home cooked meals. Wishing you a quick recovery. Hope your query is answered. Do write back if you have any doubts. Regards, Dr.Vivek

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