HAE is caused by a defect in the gene that controls a protein known as C1 inhibitor. C1 inhibitor helps regulate certain complex reactions in the body, including reactions that lead to the production of bradykinin. Bradykinin is a chemical that causes blood vessels to dilate (widen) and leak fluid into surrounding tissue. It is this leakage of fluid that is thought to cause the swelling and painful attacks associated with HAE.
In people with HAE, the body either does not produce enough C1 inhibitor or produces C1 inhibitor that does not function properly. As a result, too much bradykinin is produced, blood vessels leak fluid, and swelling and painful attacks can occur.
Berinert is a C1 esterase inhibitor. It works by replacing C1 inhibitor that is missing or not working properly in people with HAE.
Some general considerations to keep in mind during treatment with Berinert include the following:
- This medication comes as a powder that is dissolved in Sterile Water for Injection to form a liquid. It is given as an injection into a vein (an intravenous, or IV, injection).
- Berinert injections may be given by your healthcare provider or, in some cases, may be self-administered.
- You will need to receive proper training by your healthcare provider to self-inject this medication.
- The Berinert injections are given slowly, at a rate of about 4 mL per minute.
- If you self-administer Berinert to treat a laryngeal (voice box) attack, it is important to seek immediate medical attention afterward.
- If you self-administer to treat an abdominal (stomach) attack, let your healthcare provider know afterward so other possible medical causes of your symptoms can be excluded.
- You should not self-administer this medication if your attack has progressed to the point where you cannot completely prepare the dose or inject yourself with it. Instead, seek immediate medical attention.
- Once mixed for use, Berinert should be colorless and clear. Do not use the medication if it is discolored or contains particles.
- For the medication to work properly, it must be used as prescribed.