FLAG-IDA

Say it: FLAG EYE-da

Fludarabine, cytarabine, filgrastim and idarubicin

FLAG-IDA is a strong mix of four medicines given in the hospital to bring acute leukemia into remission, often before a stem cell transplant.

Also called: FLAG-Ida, FLAG IDA, FLAGIDA, IDA-FLAG, FLAG, FLAG-IDA-Ven, FLAG-IDA with venetoclax

What it is

Fludarabine helps cytarabine build up inside leukemia cells so it works better. Filgrastim (G-CSF) wakes up leukemia cells so chemotherapy can kill them. Idarubicin adds another strong way to kill the cells. The goal is remission, often followed by a stem cell transplant.

Often used for

• acute myeloid leukemia (AML) that came back or did not respond to treatment
• high risk AML as first treatment, at some centers
• acute lymphoblastic leukemia (ALL) that came back

AML use

Most often used for AML that came back or did not respond, and at some centers as a first treatment for higher risk AML. Venetoclax pills or gemtuzumab ozogamicin may be added.

ALL use

Used for ALL that came back, to try to get a new remission before a transplant or other treatment such as CAR T cell therapy.

FLAG

The same plan without idarubicin, used when a person cannot get more anthracycline medicines because of heart concerns.

The medicines in this plan

Fludarabine

Chemotherapy given through a vein over about 30 minutes each day for 5 days.

Cytarabine

Chemotherapy given through a vein over about 4 hours each day for 5 days, starting a few hours after fludarabine.

Filgrastim

A growth factor shot under the skin given during the chemotherapy days, and sometimes after, to help counts recover.

Idarubicin

Anthracycline chemotherapy given through a vein on 3 days.

How you get it

FLAG-IDA is given in the hospital through a central line. Chemotherapy lasts about 5 days, and most people stay in the hospital for about 3 to 5 weeks until blood counts recover. Most people get 1 or 2 cycles. Your schedule may be different.

A typical cycle

Days 1 to 5

Fludarabine, then cytarabine, through the IV each day. Filgrastim shots.

Days 1 to 3 (or 2 to 4)

Idarubicin through the IV.

Days 6 to 28

Blood counts drop very low. Transfusions and antibiotics are common. A bone marrow test checks the response.

Count recovery

When counts come back up, you can usually go home. Your team plans the next step, often a transplant.

Common side effects and what helps

• Very low blood counts for weeks, with a high risk of infection. You will get antibiotics, antifungal and antiviral medicines to prevent infection.
• Need for blood and platelet transfusions. These are common and expected.
• Fever, which can be from infection or from the medicines. Your team checks every fever.
• Nausea, diarrhea and poor appetite. Anti-nausea medicines are given on a schedule.
• Mouth sores. Use soft toothbrushes and gentle mouth rinses.
• Red, sore eyes from cytarabine. Steroid eye drops may be given to prevent this.
• Hair loss and tiredness. Rest when you need to.
• Rash. Tell your team so they can check it.

Call your care team right away if you have

• A fever of 100.4 degrees Fahrenheit (38 degrees Celsius) or higher, or chills
• Bleeding that will not stop, blood in your urine or stool, or many new bruises
• Trouble breathing, chest pain, or a fast or pounding heartbeat
• Trouble walking, poor balance, slurred speech or shaky hands
• New confusion, a very bad headache, trouble speaking, or weakness on one side of the body
• Redness, pain or drainage where your IV line enters the skin

Good to know

• You will have a heart test (echocardiogram) before treatment because idarubicin can affect the heart.
• After fludarabine, any blood you receive should be irradiated (treated with radiation) to prevent a rare but serious problem.
• Your team watches for tumor lysis (fast breakdown of leukemia cells) with blood tests and gives fluids and medicines to protect your kidneys.
• Nurses check your balance, speech and handwriting during cytarabine, because it can rarely affect the brain.
• Many people go on to a stem cell transplant after remission.

At home

• After you go home, check your temperature twice a day and any time you feel unwell.
• Wash your hands often and stay away from people who are sick.
• Keep all blood test and transfusion visits.
• Take your infection prevention medicines as prescribed.
• Keep your central line dry and covered.

Questions to ask

• How long will I be in the hospital?
• Will I need a second cycle?
• Will any other medicine, such as venetoclax, be added?
• Am I a candidate for a stem cell transplant?
• How will we know if the treatment worked?

Leukemia

Last updated: 2026-10-27. Medically reviewed by Veli Bakalov, MD, medical oncologist (October 2026). General education from Step by Step, the patient portal of HemeOncBuddy.