Norad 4 Injection 4 ml is used to treat low blood pressure. It contains Norepinephrine that works by constricting and narrowing blood vessels; thus, increasing blood pressure. In some cases, this medicine may cause side effects such as headaches, anxiety, tremors, difficulty in breathing, vomiting, high blood pressure, or urinary retention. Inform the doctor if you are pregnant or breastfeeding, taking any other medication, or have any pre-existing medical conditions.