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Alpha 1-proteinase inhibitor

Generic name: alpha 1-proteinase inhibitor [ AL-fa-1-PRO-tee-nase-in-HIB-i-tor ]
Brand names: Aralast NP, Glassia, Prolastin-C, Zemaira, Prolastin, Aralast
Dosage forms: intravenous powder for injection (human), intravenous solution (human)
Drug class: Miscellaneous respiratory agents

Medically reviewed by on Sep 18, 2023. Written by Cerner Multum.

What is alpha 1-proteinase inhibitor?

Alpha 1-proteinase inhibitor is a protein (alpha 1-antitrypsin) that occurs naturally in the body and helps prevent breakdown of tissues in the lungs. People who lack this protein because of a genetic deficiency can develop damage to the air sacs in the lungs (emphysema).

Alpha 1-proteinase inhibitor is used to treat alpha 1-antitrypsin deficiency in people with symptoms of emphysema.

Alpha 1-proteinase inhibitor will not cure alpha 1-antitrypsin deficiency, and may not slow the progression of emphysema.

Alpha 1-proteinase inhibitor may also be used for purposes not listed in this medication guide.

Alpha 1-proteinase inhibitor side effects

Get emergency medical help if you have signs of an allergic reaction: hives, rash; confusion, feeling light-headed; fast heartbeats, chest tightness, difficult breathing; swelling of your face, lips, tongue, or throat.

Your doctor may also prescribe epinephrine (Epi-Pen) to keep with you in case you ever have an allergic reaction to alpha 1-proteinase inhibitor.

Alpha 1-proteinase inhibitor may cause serious side effects. Stop using alpha 1-proteinase inhibitor and call your doctor at once if you have:

You may feel faint during the injection. You may need to rest for a short time afterward.

Common side effects of alpha 1-proteinase inhibitor may include:

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.


Use only as directed. Tell your doctor if you use other medicines or have other medical conditions or allergies.

Before taking this medicine

You should not use alpha 1-proteinase inhibitor if:

Tell your doctor if you have ever had:

Tell your doctor if you are pregnant or breastfeeding.

Not approved for use by anyone younger than 18 years old.

Alpha 1-proteinase inhibitor is made from donated human plasma and may contain viruses or other infectious agents. Donated plasma is tested and treated to reduce the risk of contamination, but there is still a small possibility it could transmit disease. Ask your doctor about any possible risk.

How should I use alpha 1-proteinase inhibitor?

Follow all directions on your prescription label and read all medication guides or instruction sheets. Use the medicine exactly as directed.

Alpha 1-proteinase inhibitor is injected into a vein, usually once per week.

Your first dose may be given in a medical setting where any serious side effects can be quickly treated.

Ask your doctor or pharmacist if you don't understand how to use an injection.

Be sure you understand how to properly mix the powder form of alpha 1-proteinase inhibitor with a liquid (diluent) and how to store the mixture.

Glassia is a liquid form of alpha 1-proteinase inhibitor that is not mixed with a diluent.

Prepare an injection only when you are ready to give it. Call your pharmacist if the medicine looks cloudy, has changed colors, or has particles in it.

Do not reuse a needle or syringe. Place them in a puncture-proof "sharps" container and dispose of it following state or local laws. Keep out of the reach of children and pets.

Doses are based on weight. Your dose may change if you gain or lose weight.

Store Aralast, Prolastin, or Zemaira at cool room temperature, away from moisture and heat. Use within 3 hours after mixing.

Store Glassia in the original carton in the refrigerator. Take the medicine out of the refrigerator and let it reach room temperature before preparing your dose.

Once Glassia has reached room temperature, you must use it within 1 month. Do not return it to a refrigerator.

Do not freeze alpha 1-proteinase inhibitor, and do not use it past the expiration date on the medicine label.

Throw away a vial (bottle) after one use, even if there is still medicine left inside.

Alpha 1-proteinase inhibitor dosing information

Usual Adult Dose for Alpha-1 Proteinase Inhibitor Deficiency:

60 mg/kg intravenously once a week

-Dose ranging studies using efficacy endpoints have not been performed.

Use: Chronic augmentation and maintenance therapy in adults with clinical evidence of emphysema due to hereditary deficiency of Alpha 1-Proteinase Inhibitor (alpha 1-antitrypsin deficiency)

What happens if I miss a dose?

Call your doctor for instructions if you miss a dose.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

What should I avoid while taking alpha 1-proteinase inhibitor?

Follow your doctor's instructions about any restrictions on food, beverages, or activity.

What other drugs will affect alpha 1-proteinase inhibitor?

Other drugs may affect alpha 1-proteinase inhibitor, including prescription and over-the-counter medicines, vitamins, and herbal products. Tell your doctor about all other medicines you use.

Further information

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.