Hello, A stomach pain that increases when you breathe deep and decreases when you sit upright is due to regurgitation of acid from the stomach to your foodpipe, also known as gastroesophageal reflux disease. Some lifestyle changes can help you relieve this condition. You should avoid spicy and acidic food in your diet like onions, tomatoes, citrus fruits, chilies, dark chocolate etc. In addition, do not lie down immediately after meals. In fact, have at least 2 hours of gap between dinner and bedtime. Drink more water and try to exercise regularly. Try to elevate the head end of the bed from waist up if possible. There will be no help in raising just head and not area above waist. You can also take Digene syrup (Aluminium hydroxide + Magnesium hydroxide + Carboxymethyl Cellulose) 10 ml (2 tablespoonfuls) 3-4 times a day specially after meals and before bedtime. Try antacid like Ranitidine 150 Mg (Zinetac) twice a day for 10 days. If these do not help, you should contact a Gastroenterologist for investigations regarding your condition. I hope this information helps you. Thank you for choosing HealthcareMagic for your concern. Take care. Best, Dr. Viraj Shah