Folic acid, also known as folate or vitamin B9, is an important nutrient for making new red blood cells (RBCs). It also helps your cells make more DNA and RNA so that the cells can grow and divide, as well as carry out many different tasks.

Autoimmune hemolytic anemia (AIHA) is an autoimmune disease in which you have low levels of RBCs because your immune system damages and destroys them. When you have AIHA, your body tries to make up for all the red blood cells it has lost. Because this process uses up a lot of your body’s folic acid, many people with AIHA need to take supplements containing folic acid to make sure they have enough of this nutrient.

Folic Acid and Red Blood Cells

Your body relies on folic acid as it continually makes new RBCs from other blood cells in the bone marrow (spongy tissue found inside certain bones). This B vitamin is also important for helping immature RBCs develop into fully formed cells that can carry oxygen around the body.

Typically, your immune system creates proteins called antibodies that can identify and attack germs such as bacteria or viruses. With AIHA, your immune cells mistakenly make antibodies that attack your RBCs, causing them to break apart in a process known as hemolysis.

To replace RBCs, your body needs several nutrients, including vitamin B12, iron, and folic acid. If you don’t have enough folic acid stored within your body, you won’t be able to produce enough new cells. Folic acid supplements can treat a folic acid deficiency, helping your body keep up RBC levels — or prevent you from developing a deficiency in the first place.

Taking Folic Acid for AIHA

Typically, experts conduct various studies and clinical trials to test whether potential treatments are helpful and safe for people with a specific condition. However, experts have not yet conducted much research to investigate the effect of folic acid supplements on AIHA.

Despite the lack of clear evidence, most experts recommend that people with AIHA take folic acid supplements, and most doctors who treat AIHA believe that maintaining high levels of this vitamin helps improve the condition, especially for those with severe anemia.

Folic acid may help with both types of AIHA — both warm AIHA and cold AIHA (including cold agglutinin disease and paroxysmal cold hemoglobinuria).

How Much Folic Acid Do You Need?

Experts recommend that most healthy adults get 400 micrograms (mcg) of folic acid per day. Those who are breastfeeding need 500 mcg, and pregnant people need 600 mcg daily. Children generally need lower levels of this nutrient.

You may need much higher amounts of folic acid if you have AIHA. Many doctors recommend that people with this autoimmune disorder consume at least 1 milligram (mg) of this nutrient every day. This is the equivalent of 1,000 mcg of folic acid. It may also be important to take extra folic acid if you are taking steroid medications for long periods.

In some cases, doctors may prescribe much higher amounts of folic acid. “I am taking two 5-mg tablets of folic acid per day,” one member said.

Always follow your doctor's instructions regarding how much folic acid to take. Your health care team may also suggest taking additional supplements such as calcium or vitamin D, depending on your needs.

Symptoms of a Folic Acid Deficiency

If folic acid levels in your body drop, you might develop painful sores in your mouth, such as on your tongue. Your skin, fingernails, or hair may also change in appearance. Finally, you may experience digestive system problems.

Tell your doctor if you notice any of these symptoms. You might need to take more folic acid to treat these issues.

How To Get More Folic Acid

You can find many folic acid or vitamin B9 supplements sold over the counter. Folic acid is usually included in multivitamins, but the amount might be too little if you have AIHA. While taking folic acid, it’s a good idea to make sure you’re also getting enough vitamin B12.

In addition to suggesting you take folic acid supplements, your doctor may recommend AIHA treatments such as:

• Steroids (prednisone, for example)
• Targeted therapies like rituximab (Rituxan), bortezomib (Velcade), or eculizumab (Soliris)
• Immunosuppressive drugs such as cyclosporin A (Neoral)
• Chemotherapy medications such as fludarabine (Fludara) or cyclophosphamide (sold as Cytoxan and Neosar)
• Surgery such as splenectomy (a procedure to remove the spleen)
• Blood transfusions

One myAIHAteam member, who had recently returned home from the hospital, wrote, “I am continuing my prescribed at-home treatment protocol, including the oral prednisolone (Omnipred), folic acid tabs, pantoprazole (Protonix) tabs in the evenings, co-trimoxazole (Septrin) tabs, and Nystatin oral suspension.”

Foods With Folic Acid

You can also get folic acid from your diet. Foods that contain high levels of this vitamin include:

• Beef liver
• Green vegetables such as spinach, lettuce, broccoli, Brussels sprouts, and asparagus
• Tomatoes and tomato juice
• Oranges and orange juice
• Beans and nuts, including black-eyed peas, green peas, kidney beans, and peanuts
• Grain-based foods with added folic acid, including rice, bread, breakfast cereal, and pasta

However, if you need high levels of folic acid due to AIHA or other factors, it’s better to take supplements rather than rely on your diet. Your digestive system absorbs 85 percent or more of the folic acid you eat in supplement form but just 50 percent of the folic acid present in foods.

Potential Side Effects of Folic Acid Supplements

Folic acid is usually safe and doesn’t lead to major issues. However, in some cases, it may cause side effects such as:

• Nausea
• Appetite loss
• A bad taste in your mouth
• Insomnia
• Confusion

In rare cases, supplements that contain folic acid may lead to an allergic reaction, which could cause hives (an itchy rash), redness, or breathing problems.

Folic acid can’t be combined with certain medications, including antiseizure drugs, antimalarial drugs, methotrexate, or barbiturates (medications that calm the nervous system). Make sure that your doctor and pharmacist know about all the medications and supplements you are taking so that they can identify any potential problems.

Talk With Others Who Understand

On myAIHAteam, people with AIHA and their loved ones come together to ask questions, give advice, and share their stories with others who understand life with this condition.

Have you tried folic acid supplements to treat autoimmune hemolytic anemia? Do you think they had an impact on your symptoms? Share your experience in the comments below, or start a conversation by posting on myAIHAteam.