Treatment of acute attacks
Painless swelling affecting the arms, legs and trunk may not require treatment if they do not prevent work or school activities.
Swelling of the abdomen, face or airway should be treated promptly with intravenous injections of C1 Inhibitor concentrate or a subcutaneous injection of Icatibant.
Acute attack medications
C1 Inhibitor Concentrate – trade name: Berinert
Berinert is a concentrate of C1 Inhibitor. Berinert is a blood product which raises the level of C1 Inhibitor in the blood and halts the progress of an acute attack of oedema.
Berinert is given by slow intravenous injection, either in hospital by a medical professional, or at home if the patient has been trained in home therapy.
Berinert is licensed in the UK for use in adults and children.
C1 Inhibitor Concentrate – trade name: Cinryze
Cinryze is another plasma product that is licensed for use in the UK.
Recombinant C1 Inhibitor (conestat alpha) – trade name: Ruconest
Ruconest is a recombinant C1 inhibitor which is derived from the milk of female rabbits that have been genetically altered to produce the human C1 Inhibitor protein.
Ruconest is given by slow intravenous injection. It is not suitable for patients who have a rabbit allergy.
Icatibant – trade name: Firazyr
Icatibant is produced as a synthetic protein (a non blood product), and it is effective in halting an attack of oedema.
Icatibant is given by subcutaneous injection (an injection into the tissues just below the skin).
Icatibant comes in a pre-filled 3 ml syringe ready for injection. More than one syringe may be required to fully resolve attacks.
Icatibant is licensed for adults for administration by a medical professional or at home if the patient has been trained in home therapy.
Short term prevention of acute attacks
It is important to discuss management of possible precipitating factors with your specialist.
Danazol or Oxandrolone or C1 Inhibitor concentrate may be used to prevent an attack.
If a person with HAE or AAE requires surgical procedures (including dental treatment) actions should be taken to prevent a possible attack.
The person should receive an infusion of concentrate prior to surgery. There will be a slight increase in the risk of swelling in the 3 days following surgery. This should be treated with C1 Inhibitor or Icatibant in the usual way.
Long term preventative treatment
The frequency and severity of attacks of angioedema can be reduced by attenuated androgens such as Danazol and Oxandrolone, or by Tranexamic Acid. Your doctor will discuss these treatments with you.
Preventative Medications – drugs used to reduce the incidence and severity of an attack
Danazol may be used to reduce the level of HAE attacks. However, Danazol is an attenuated androgen which may cause unacceptable side effects, particularly in females. It is important to keep the doses of the medication as low as possible, and side effects should be reported as they are usually reversible if danazol is stopped promptly.
Oxandrolone is also an attenuated androgen that is used to reduce the level of HAE attacks. Oxandrolone may be helpful even if Danazol has not been effective, or if Danazol has not been well tolerated.
Attenuated androgens, if used wisely, can be well tolerated even in women, and can improve quality of life for HAE patients.
Tranexamic Acid can be used in children and adults in an effort to reduce the number of attacks of angioedema.
Maintenance therapy using C1 Inhibitor concentrate
Occasionally regular injections of C1 Inhibitor may be needed as a preventative measure.
The use of regular injections of C1 Inhibitor may be recommended in:
- Cases of frequent severe attacks of angioedema where attenuated androgens are insufficient or unacceptable
- In frequent severe attacks in pregnancy
- In severe HAE in children
Home therapy for HAE patients
Suitable patients who get frequent severe attacks of HAE will be offered training to give their acute attack medications at home.