Table of ContentsView AllTable of ContentsTypesSymptomsCausesDiagnosisTreatmentPrognosis
Table of ContentsView All
View All
Table of Contents
Types
Symptoms
Causes
Diagnosis
Treatment
Prognosis
Macrocytic anemia is a condition in which red blood cells are too large. The enlarged red blood cells are not fully developed and do not function the way they should. This causes diminished oxygen delivery to all cells of the body, resulting in fatigue and low energy.
Sometimes long-term prevention is necessary with diet or supplements or with other lifestyle modifications, such as avoiding alcohol.
Types of Macrocytic Anemia
These types are megaloblastic macrocytic anemia and non-megaloblastic macrocytic anemia, which are:
What Are the Symptoms of Macrocytic Anemia?
Macrocytic anemia usually develops slowly over time. Red blood cells normally circulate for several months before the body naturally breaks them down and makes new ones. It takes a while for the enlarged red blood cells to cause symptoms, because there are usually healthy red blood cells in circulation as well.
With macrocytic anemia, the large red blood cells circulate throughout the body, but they do not deliver an adequate amount of oxygen to the body’s tissues. This causes nonspecific symptoms that can progressively worsen.
Effects can include:
If you have a history or risk factors for macrocytic anemia, it’s important that you are alert to these symptoms. They can be indicators that you are developing anemia—which is a diminished red blood cell number or function.
Causes of Macrocytic Anemia
There are several causes of macrocytic anemia. You can develop the condition due to just one of the causes, but you can also have more than one cause.
Verywell / Zoe Hansen
Reasons that macrocytic anemia may develop include:
Liver disease, alcohol use,hypothyroidism(underactive thyroid gland),myelodysplastic syndrome(bone marrow disease),leukemia(blood cancer), and some other types of cancer can also cause macrocytic anemia.
How Macrocytic Anemia Develops
Macrocytic anemia occurs when red blood cells are developing, but they do not progress to a mature and fully functioning state.
Megaloblastic macrocytic anemia develops because vitamin B12 and folate are needed for the development of the genetic components of red blood cells. When these vitamins are lacking, the cellular portion of the red blood cell develops, but the genetic component does not adequately develop. This makes the cell large, but not properly functional.
How Macrocytic Anemia Is Diagnosed
Macrocytic anemia doesn’t usually cause physical signs that are detected with a clinical examination. You might have other signs that are associated with the underlying cause.
For example, if you have severe liver disease, you could havejaundice(skin and whites of the eyes are yellowish), or you could haveenlarged lymph nodesif you have cancer.
If you have macrocytic anemia associated with alcohol use, you may haveperipheral neuropathy(nerve damage usually in the hands and feet that affects sensation or movement) due to alcohol use and/or signs of liver damage. However, these physical signs develop at late stages, and macrocytic anemia can develop before these changes.
Macrocytic anemia can be diagnosed with acomplete blood count (CBC), red blood cell indices, and a blood smear.
Tests that can identify macrocytic anemia:
Generally, a CBC is a routine blood test that is often part of a yearly physical, and it is also done to assess problems such as persistent fatigue, fevers, and unexplained weight loss. A blood smear or reticulocyte count may be done when there is a specific concern about the health or function of the red blood cells.
Medication MonitoringMedications that can cause macrocytic anemia do not always cause this side effect for everyone, so your doctors may monitor your CBC if you are taking a medication that puts you at risk.
Medication Monitoring
Medications that can cause macrocytic anemia do not always cause this side effect for everyone, so your doctors may monitor your CBC if you are taking a medication that puts you at risk.
Other diagnostic tests you might have will be tailored to your situation.
Tests your healthcare provider may order for you include:
Treatment for Macrocytic Anemia
The treatment of macrocytic anemia depends on the cause. Treatment and prevention are closely linked together.
Treatments can include:
The treatment can help resolve the range of effects of the underlying condition, including macrocytic anemia.
Prognosis: What to Expect
Summary
Macrocytic anemia can cause the same symptoms as most types of anemia, including low energy and generalized weakness. This condition can develop due to nutritional deficiencies, cancer, medication, alcohol, liver disease, and hyperthyroidism.
It can be diagnosed with blood tests. The treatment is focused on the management of the underlying condition. After treatment, anemia can resolve over the course of weeks or months, and it may require ongoing treatment.
A Word From Verywell
If you have symptoms of anemia, it’s important that you get medical attention. The effects are vague and can develop due to many different reasons. Once you know the cause of your symptoms, you can get started on your treatment.
You should feel an improvement in your symptoms, and you might notice a recurrence of symptoms if you ever develop macrocytic anemia again. Depending om the cause an severity of your anemia you can remain on treatment for the long term, or you can resume treatment as needed.
3 SourcesVerywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Green R, Datta Mitra A.Megaloblastic anemias: Nutritional and other causes.Med Clin North Am. 2017 Mar;101(2):297-317. doi:10.1016/j.mcna.2016.09.013Nagao T, Hirokawa M.Diagnosis and treatment of macrocytic anemias in adults.J Gen Fam Med.2017 Apr 13;18(5):200-204. doi:10.1002/jgf2.31Htut TW, Thein KZ, Oo TH.Pernicious anemia: Pathophysiology and diagnostic difficulties.J Evid Based Med. 2021;14(2):161-169. doi:10.1111/jebm.12435
3 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Green R, Datta Mitra A.Megaloblastic anemias: Nutritional and other causes.Med Clin North Am. 2017 Mar;101(2):297-317. doi:10.1016/j.mcna.2016.09.013Nagao T, Hirokawa M.Diagnosis and treatment of macrocytic anemias in adults.J Gen Fam Med.2017 Apr 13;18(5):200-204. doi:10.1002/jgf2.31Htut TW, Thein KZ, Oo TH.Pernicious anemia: Pathophysiology and diagnostic difficulties.J Evid Based Med. 2021;14(2):161-169. doi:10.1111/jebm.12435
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
Green R, Datta Mitra A.Megaloblastic anemias: Nutritional and other causes.Med Clin North Am. 2017 Mar;101(2):297-317. doi:10.1016/j.mcna.2016.09.013Nagao T, Hirokawa M.Diagnosis and treatment of macrocytic anemias in adults.J Gen Fam Med.2017 Apr 13;18(5):200-204. doi:10.1002/jgf2.31Htut TW, Thein KZ, Oo TH.Pernicious anemia: Pathophysiology and diagnostic difficulties.J Evid Based Med. 2021;14(2):161-169. doi:10.1111/jebm.12435
Green R, Datta Mitra A.Megaloblastic anemias: Nutritional and other causes.Med Clin North Am. 2017 Mar;101(2):297-317. doi:10.1016/j.mcna.2016.09.013
Nagao T, Hirokawa M.Diagnosis and treatment of macrocytic anemias in adults.J Gen Fam Med.2017 Apr 13;18(5):200-204. doi:10.1002/jgf2.31
Htut TW, Thein KZ, Oo TH.Pernicious anemia: Pathophysiology and diagnostic difficulties.J Evid Based Med. 2021;14(2):161-169. doi:10.1111/jebm.12435
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