Hi and welcome. If your BS goes too low when on Gliclazide then the dose may be a little too high. Gliclazide itself doesn't affect weight loss or gain but enables the pancreas to produce more insulin and this does enable the body to metabolise carbs. These carbs can cause weight gain. When T2, reducing weight may help control BS as it reduces insulin resistance. Gliclazide is prescribed when the pancreas is under-producing insulin so the mechanism is different. Don't just stop the Gliclazide but ask the DN to review the dosage.