<s>[INST] Is it true that a gastric bypass patient has to inject themselves with blood thinner for 2 weeks after surgery? [/INST] The patients with morbid obeisty has tendency for deep vein thrombosis. That is why those who have varicose veins, ulcers on legs , those who are extermely overweight or those with extremely high BMI,they are instructed to keep hydration well, use stockings and in selected cases they are advised to take blood thinners for 2-3 weeks based on risk of deep vein thrombosis. Source: LOC. Link: https://obesityasia.com/faqs/. Field: Endocrinology. Disease: Obesity </s>