Roferon A 3Million IU Injection is used in the treatment of follicular lymphoma and hairy cell leukemia. It works by altering cell function/growth and the body's natural defenses (immune system) in many ways. Roferon A 3Million IU Injection is given as an injection by a qualified medical professional. Your doctor will decide what dose is necessary and how often you need to take it. This will depend on what you are being treated for and may change from time to time. You should take it exactly as your doctor has advised. Taking it in the wrong way or taking too much can cause very serious side effects. It may take several weeks or months for you to see or feel the benefits but do not stop taking it unless your doctor tells you to. Headache, flu-like symptoms, sweating, fatigue, and muscle pain are some common side effects of this medicine. This medicine may reduce the number of blood cells (white blood cells) in your blood, thereby, increasing the susceptibility to infections. Regular blood tests are required to check your blood cells along with heart, liver and blood sugar level. You must have to inform your doctor immediately if you notice mood change, depression, and change in vision. Before taking it, tell your doctor if you have heart disease, liver, or kidney problems or are taking any medicines to treat infections. Many other medicines can affect, or be affected by, this medicine so let your healthcare team know all medications you are using. This medicine is not recommended during pregnancy. The use of effective contraception by both males and females during treatment is important to avoid pregnancy.