Not Medical Advice: According to American Red Cross, after the transfusion you should drink an extra four (8 ounce) glasses of liquids and avoid alcohol over the next 24 hours.
You will also have to stay a short time after the transfusion ends so healthcare providers can watch for signs of a reaction. You may feel some pain or see bruises near the site for a few days after the transfusion.
Apply ice to decrease pain and swelling. Use an ice pack, or put ice in a plastic bag and wrap a towel around it. Apply the ice pack or wrapped bag to your transfusion site for 20 minutes each hour or as directed.
Here's what you need to know about a blood transfusion shared by Drugs.com.