Macrocytic anemia is a blood disorder that happens when your bone marrow produces abnormally large red blood cells. These abnormal blood cells lack nutrients red blood cells need to function normally. Macrocytic anemia isn’t a serious illness but it can cause serious medical issues if left untreated.
Macrocytic anemia is a blood disorder that happens when your bone marrow produces abnormally large red blood cells. These abnormal blood cells lack nutrients red blood cells need to function normally. There are two types of macrocytic anemias. They develop when your body lacks certain nutrients. Macrocytic anemia isn’t a serious illness but it can cause serious medical issues if left untreated.
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The two most common forms of macrocytic anemia are megaloblastic macrocytic anemia and non-megaloblastic macrocytic anemia.
The most common medical conditions are:
People may develop macrocytic anemia when they don’t get enough vitamin B12 and/or folate (vitamin B9) to create healthy red blood cells, or they have medical conditions that prevent their bodies from absorbing those nutrients.
Healthcare providers diagnose macrocytic anemia by doing a physical examination and asking questions about your symptoms. They may also perform the following blood tests:
Healthcare providers evaluate the condition’s underlying cause to develop treatment so your bone marrow can create healthy red blood cells. For example, you may have macrocytic anemia because you’re not eating enough food or your diet lacks important nutrients such as vitamin B12 or folate (vitamin B9). Sometimes, people are eating well, but there’s something keeping their bodies from absorbing nutrients. If that’s your situation, your healthcare provider may prescribe supplements. They may recommend you take supplements until blood tests show your bone marrow is developing healthy red blood cells.
If you have macrocytic anemia because you have an underlying condition, your healthcare provider will treat the underlying condition. For example, some people have conditions that keep their bodies from absorbing essential nutrients.
Many people develop macrocytic anemia because they drink a lot of alcohol. In that case, your healthcare provider may prescribe medical treatment and recommend treatment to help you manage your alcohol intake.
Macrocytic anemia happens for several reasons, including underlying illness that you may not be able to prevent. If you don’t have an underlying illness, however, there are steps you can take to reduce your risk and possibly prevent macrocytic anemia, such as:
Most people recover from macrocytic anemia after receiving vitamin supplements. Prognosis, or expected outcome, for people who have underlying conditions depends on the underlying condition and their situation.
Take care of yourself by:
A note from Cleveland Clinic
People develop macrocytic anemia when they don’t get enough nutrients to help their bodies develop healthy red blood cells. Macrocytic anemia can happen if people follow certain diets or have certain underlying conditions. Macrocytic anemia isn’t a serious illness but it can cause serious medical issues. You may be able to prevent macrocytic anemia by eating well. If you’re concerned about macrocytic anemia, ask your healthcare provider for help. They’ll assess your situation and recommend ways you can improve your diet. If you have macrocytic anemia, your healthcare provider will prescribe supplements to replace missing nutrients. They’ll also help you develop habits to keep you healthy.
Last reviewed by a Cleveland Clinic medical professional on 05/16/2022.
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