Anemia is a low level of healthy red blood cells (RBCs). RBCs carry oxygen from the lungs to the rest of the body. When RBCs are low, the body does not get enough oxygen.

Aplastic anemia is a type of anemia caused by problems with bone marrow. It is a rare condition. It can range from moderate to severe. In some, it can be life-threatening.

Location of Active Bone Marrow in an Adult
nucleus factsheet image

Copyright © Nucleus Medical Media, Inc.


Blood cells start as stem cells in the bone marrow. Aplastic anemia is caused by damage to these stem cells. The damaged cells cannot develop as RBCs and levels in the body begin to drop. It is believed this happens in most because of a problem in the immune system. Sometimes drugs, viruses, or toxins may play a role.

Risk Factors

The risk of aplastic anemia is higher in those with:

  • Exposure to certain toxins such as those in gas, paint, oil and coal emissions, and industrial solvents
  • High-dose radiation and chemotherapy treatments
  • Certain viruses
  • Certain medicine such as antibiotics, some illegal drugs
  • Medicine used to treat rheumatoid arthritis
  • Bone marrow diseases
  • Pregnancy


Aplastic anemia may cause:

  • Fatigue
  • Shortness of breath with activity
  • Weakness
  • Rapid heart rate
  • Pale skin
  • Easy bruising
  • Nosebleeds and bleeding gums
  • Lengthy bleeding from cuts
  • Skin rash
  • Fever
  • Shortened attention span


You will be asked about your symptoms and past health. A physical exam will be done. Blood tests will show the level of RBCs. A bone marrow biopsy will also be done. It will show where the problems are starting and rule out other problems.

Other tests may be needed to look for a cause.


Treatment will depend on the cause, age, and overall health. The main goal is to increase the number of red blood cells. Treatment for aplastic anemia from other causes may include:

Blood Transfusions

Healthy blood from a donor can quickly replace red blood cells. It will help to temporarily relieve symptoms. However, it is not a cure. Once those blood cells wear down, the anemia will occur again.

Immune Suppressing Medicine

Medicine can change or slow the immune system. It will help if stem cell damage is caused by immune system problems. Slowing the immune system will give bone marrow time to recover. It should then be able to make red blood cells again.

The medicine may be used along with steroids. This treatment may be given during a short stay in the hospital.

Bone Marrow Transplantation

Badly damaged bone marrow may need to be replaced. Marrow from a donor will need to be matched. The healthy bone marrow should be able to make healthy RBCs again.

Stopping Cause

Sometimes the cause is known and can be stopped. Medicine may be stopped. Exposure to radiation or chemicals may also be reduced. The doctor may choose to monitor the anemia until the bone marrow can recover.


Most cases of aplastic anemia cannot be prevented.

For others, limit exposure to toxins when possible. Use proper care when you are around things like gas, paint, oil, coal emissions, and industrial solvents.


Aplastic Anemia and MDS International Foundation

National Heart, Lung, and Blood Institute


Aplastic Anemia and Myelodysplasia Association of Canada

The College of Family Physicians of Canada


Aplastic anemia. EBSCO DynaMed website. Available at: Updated December 20, 2016. Accessed February 10, 2020.

DeZern AE, Guinan EC. Aplastic anemia in adolescents and young adults. Acta Haematol. 2014;132(3-4):331-9.

Explore aplastic anemia. National Heart, Lung, and Blood Institute website. Available at: Accessed February 10, 2020.

Killick SB, Bown N, Cavenagh J, et al; British Society for Standards in Haematology. Guidelines for the diagnosis and management of adult aplastic anaemia. Br J Haematol. 2016 Jan;172(2):187-207.

Last reviewed September 2019 by EBSCO Medical Review Board Marcin Chwistek, MD  Last Updated: 8/5/2020