Pernicious anemia is a type of vitamin B12 deficiency anemia that happens when your body can’t absorb enough vitamin B12. This essential nutrient helps your body make red blood cells and supports nerve function.
When vitamin B12 levels are too low, it can lead to symptoms like fatigue, weakness and nerve-related changes.
We spoke with Andrea Padilla, MD, a family medicine physician with Banner – University Medicine, to better understand pernicious anemia and how it’s treated.
Symptoms of pernicious anemia (vitamin B12 deficiency)
Symptoms can develop slowly and may include:
- Fatigue
- Weakness
- Pale or yellowish skin
- Shortness of breath
- Dizziness
- Numbness or tingling in the hands and feet
- Difficulty concentrating
- Mood changes
“People often feel tired, have yellowed skin and may have neurologic abnormalities such as peripheral neuropathy or slowed cognition,” Padilla said.
What causes pernicious anemia?
Pernicious anemia occurs when your body doesn’t have enough intrinsic factor, a protein made in the stomach that helps absorb vitamin B12.
“You could develop pernicious anemia if you don’t have enough intrinsic factor,” Padilla said.
This often happens because the immune system attacks the stomach cells that produce intrinsic factor. Experts aren’t sure exactly why this occurs.
Other contributing factors may include:
- Family history
- Autoimmune conditions
- Digestive disorders such as celiac disease or Crohn’s disease
- Gastric bypass surgery or other stomach conditions
Who is at risk for pernicious anemia?
You may be more likely to develop pernicious anemia if you:
- Are over age 60
- Have Northern European or Scandinavian ancestry
- Have autoimmune conditions such as type 1 diabetes, Hashimoto’s thyroiditis or Addison’s disease
- Have a family history of the condition
How pernicious anemia is diagnosed
Your health care provider will use a combination of tests, including:
- Medical history and symptoms: Reviewing fatigue, weakness or neurological symptoms
- Physical exam: Checking for signs such as pale skin or nerve changes
- Blood tests: A complete blood count (CBC) and vitamin B12 levels
- Intrinsic factor antibody test: To confirm autoimmune causes
- Additional testing: Iron, folate or bone marrow tests if needed
How pernicious anemia is treated
Treatment focuses on restoring vitamin B12 levels.
“If you have pernicious anemia, you will need to take vitamin B12 for life,” Padilla said.
Treatment options include:
- Vitamin B12 injections
- Nasal sprays
- Oral supplements (in some cases)
You’ll also need regular follow-up to monitor your levels and adjust treatment as needed.
Can diet alone treat pernicious anemia?
No. Because pernicious anemia affects how your body absorbs vitamin B12, diet alone is not enough to treat it.
However, eating foods rich in vitamin B12, such as meat, fish, dairy and fortified foods, can support overall health alongside treatment.
Possible complications of pernicious anemia
Without treatment, pernicious anemia can lead to serious complications, including:
- Neurological problems: Nerve damage, balance issues and memory loss
- Heart issues: Irregular heartbeat or heart strain
- Cognitive decline: Memory and thinking problems
- Pregnancy complications: Risks for both mother and baby
- Increased infection risk: Due to reduced immune function
“These issues can become permanent if pernicious anemia isn’t treated,” Padilla said.
Frequently asked questions about pernicious anemia
What is the main cause of pernicious anemia?
An autoimmune condition that prevents your body from absorbing vitamin B12.
What are early symptoms of vitamin B12 deficiency?
Fatigue, weakness and tingling in the hands and feet.
Is pernicious anemia serious?
It can be if untreated, but it is manageable with proper care.
Can pernicious anemia be cured?
It is a lifelong condition, but symptoms can be controlled with treatment.
The bottom line
Pernicious anemia is a vitamin B12 deficiency that can lead to serious health problems if left untreated.
With proper diagnosis and ongoing treatment, most people can manage symptoms and maintain their health.
If you have symptoms of vitamin B12 deficiency, talk to a Banner Health provider about testing and treatment options.
