It is clear from what a friend of yours is going through that something's wrong with the blood passing through the digestive tract and coming out of the mouth. ideally, it must be an ulcer in the stomach, inflammation, or even some sort of unwanted microorganisms. Your friend needs to be checked by a gastroenterologist as soon as possible so that the exact cause can be figured out and the right medication be given to them. 

It seems that you have an ailment known as an anal crack. This condition is characterized by cracks in the skin around the anus, which can lead to blood and/or injury in the rectum. This may be from being constipated, having diarrhea, or simply surviving hard stools. To relieve the pain and the healing process, you should see a dietician who will give you foods rich in fiber. Also, a glass of water every day and the use of over-the-counter creams to cover the corroded area can be used to help ease the pain and promote the area to heal. For sure, the area troubles you, however, you are urged to seek help if the techniques have failed and no improvement has been noticed.

You may have acid reflux. This is when the stomach contents come back up into your throat and cause a burning sensation as well as coughing. It may also make you feel sick to your stomach or give you chest pains. You should avoid eating large meals, such as spicy or fatty foods. Moreover, you shouldn’t lie down immediately after eating. Drinking lots of water helps too. If none of these work, visit a gastroenterologist.

I think you might have a stomach upset. When you take birth control pills with L Thyroxin, you might experience diarrhea. This could mean that the combo is affecting your gut. Keep yourself hydrated and consider taking the drugs at different times during the day. If it doesn’t stop, talk to a doctor so they can advise accordingly.