What is alpha-1 antitrypsin deficiency?

Alpha-1 Antitrypsin Deficiency

Alpha-1 antitrypsin deficiency: Overview

Alpha-1 antitrypsin (AAT) is a protein normally found in the lungs and the bloodstream. It helps protect the lungs from diseases such as emphysema and chronic obstructive pulmonary disease (COPD). Some people do not make enough of this protein or they make an abnormal type of AAT, either of which can cause AAT deficiency. These people are more likely to have lung diseases and will get them at a younger-than-normal age (30 to 40 years old). Some types of abnormal AAT can also damage the liver. AAT deficiency is a rare disorder and is the only known genetic (inherited) factor that increases your chances for developing emphysema.

Alpha-1 antitrypsin deficiency is caused by a change, or mutation, in the gene that tells the body how to make alpha-1 antitrypsin. There are many kinds of possible changes in this gene, but only a few cause problems. To have this condition, you have to get the changed gene from both parents.

If you receive only one changed gene, you do not have the disease but are a carrier. The good copy of the gene you received from your other parent is enough to tell your body how to properly make alpha-1 antitrypsin. Some people who carry the changed gene may have very mild symptoms of the deficiency.

Treatment for alpha-1 antitrypsin deficiency involves avoiding substances—especially cigarette smoke—that could harm your lungs. Also try to avoid dust and workplace chemicals. You also may want to avoid alcohol because of the risk of liver damage. Exercise can improve your stamina and overall health. You may also need medicines and other treatments to help you breathe easier and stay as healthy and strong as you can.

The only treatment available for the lack of the protein is plasma containing alpha-1 antitrypsin. This is usually given only to people who have very low levels of AAT in their blood. It is not clear that this treatment is any better than avoiding smoke and other lung-damaging chemicals. The plasma is made from the blood of many donors and is treated to reduce the chance of spreading an infectious disease. You receive the plasma through an I.V., usually every 3 to 4 weeks for life.

How is alpha-1 antitrypsin deficiency treated?

It is extremely important that you do not smoke if you have an AAT deficiency. Smokers with this condition may suffer devastating disease at a young age. People with this condition who have never smoked usually do not have significant symptoms at any age.

Treatment for COPD may include medicines to help you breathe easier. It may also include pulmonary rehabilitation. This means learning exercise, eating, and breathing tips and other ways to help yourself stay as healthy and strong as you can. And your doctor may suggest that you have injections of man-made alpha-1 antitrypsin protein (also called an alpha-1 proteinase inhibitor) that has been obtained from human plasma. Examples include Aralast, Prolastin, and Zemaira. To be considered for this treatment, you must meet the following guidelines:

  • Your blood levels of the alpha-1 antitrypsin enzyme are less than 11 µmol/L (micromoles per liter).
  • DNA testing shows that your body does not produce enough of the enzyme or produces an enzyme that does not work properly.
  • You do not smoke or have stopped smoking.
  • You have difficulty breathing because of COPD or emphysema.

Injections of replacement alpha-1 antitrypsin are given either weekly or every 2 to 4 weeks. Benefits of the therapy are not clear at this time.

How can you care for yourself when you have an alpha-1 antitrypsin deficiency and emphysema?

To stay healthy

  • Do not smoke. This is the most important step you can take to prevent damage to your lungs. If you already smoke, it is never too late to stop. If you need help quitting, talk to your doctor about stop-smoking programs and medicines. These can increase your chances of quitting for good.
  • Avoid secondhand smoke and air pollution. Try to stay inside with your windows closed when air pollution is bad.
  • Talk to your doctor before you fly or travel to places that are at high altitudes.
  • Do not use aerosol products such as aerosol hair spray, spray paint, or aerosol cleaning products.
  • Avoid infections such as COVID-19, colds, and the flu.
    • Wash your hands often.
    • Stay up to date on your COVID-19 vaccines.
    • Get a flu vaccine each year, as soon as it is available. Ask those you live or work with to do the same so they will not get the flu and infect you.
    • Get the pneumococcal vaccine. It may keep you from getting pneumonia. And if you do get pneumonia, you probably will not be as sick.
    • Make sure you are current on the whooping cough (pertussis) vaccine to help prevent whooping cough.


  • Take your medicines exactly as prescribed. Call your doctor if you think you are having a problem with your medicine. You will get more details on the specific medicines your doctor prescribes.
  • If you use inhaled medicines, a spacer may help you get more medicine into your lungs. Ask your doctor or pharmacist if a spacer is right for you. If so, ask them how to use it properly.
  • You may take medicines such as:
    • Alpha-1 antitrypsin (AAT) replacement (such as Prolastin). This may slow down lung disease in people with AAT deficiency. You get these medicines through a tube in your vein, called an I.V.
    • Bronchodilators (such as albuterol or metaproterenol). These help open your airways and make breathing easier. Bronchodilators are either short-acting (they work for 4 to 9 hours) or long-acting (they work 12 to 24 hours). You inhale most bronchodilators, so they start to act quickly. Always carry your short-acting inhaler with you in case you need it.
    • Corticosteroid medicines (such as budesonide or prednisone). These reduce airway swelling. They come in inhaled or pill form.
  • Do not take any vitamins, over-the-counter drugs, or herbal products without talking to your doctor first.
  • If your doctor prescribes antibiotics for an infection, take them as directed. Do not stop taking them just because you feel better. You need to take the full course of antibiotics.


  • Get regular exercise. Walking is an easy way to get exercise. Start out slowly, and walk a little more each day.
  • Pay attention to your breathing. You are exercising too hard if you cannot talk while you are exercising.

Mental health

  • Having AAT deficiency can bring up many emotions. It is common to feel frightened, angry, hopeless, or helpless. It may help to talk with your family, friends, or a therapist about your feelings. Talking openly about your feelings can help you cope. If you think you are depressed, ask your doctor for help. Treatment may help you feel better.

What puts you at risk for alpha-1 antitrypsin deficiency?

Your doctor may suspect you have an AAT deficiency if you:

  • Develop emphysema at 45 years of age or younger.
  • Develop emphysema without having any recognized risk factors, such as smoking or inhaling industrial dust or chemical fumes over a long period of time.
  • Develop emphysema, and X-rays show less density in the lungs than normal (basilar hyperlucency).
  • Develop unexplained liver disease.
  • Have a family history of emphysema, bronchiectasis, liver disease, or inflammation of the fat under the skin (necrotizing panniculitis).
  • Have bronchiectasis without an evident cause.

What is alpha-1 antitrypsin deficiency?

Alpha-1 antitrypsin (AAT) is a protein normally found in the lungs and the bloodstream. It helps protect the lungs from the damage caused by inflammation that can lead to emphysema and chronic obstructive pulmonary disease (COPD). People whose bodies do not produce enough of this protein (AAT deficiency) are more likely to develop emphysema and to do so at a younger-than-normal age (30 to 40 years old). AAT deficiency is a rare disorder and is the only known genetic (inherited) factor that increases your risk of developing COPD.

Alpha-1 antitrypsin deficiency and emphysema: When to call

Call 911 anytime you think you may need emergency care. For example, call if:

  • You have severe trouble breathing.

Call your doctor now or seek immediate medical care if:

  • You have new or worse shortness of breath.
  • You are coughing more deeply or more often, especially if you notice more mucus or a change in the color of your mucus.
  • You cough up blood.
  • You have new or increased swelling in your legs or belly.
  • You have a fever.

Watch closely for changes in your health, and be sure to contact your doctor if you have any problems.

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The content above contains general health information provided by Healthwise, Incorporated, and reviewed by its medical experts. This content should not replace the advice of your healthcare provider. Not all treatments or services described are offered as services by us. For recommended treatments, please consult your healthcare provider.