C1 esterase inhibitor

This is an important test to help diagnose HAE.

Venous blood
1 tests included
7 days turnaround



About C1 esterase inhibitor

What is the C1 esterase inhibitor?

The C1 esterase inhibitor (C1-INH) is a protein which inhibits the activity of the C1 protein. The C1 protein is part of the complement system, a term for a group of proteins in the blood and body fluids which are part of the innate immune system. The complement system helps the body to fight infections by promoting inflammation, facilitating removal of pathogens, such as bacteria and clearance of cell debris. The C1-INH regulates the complement system and acts as an anti-inflammatory.

Levels of the C1-INH are reduced in a condition called hereditary angioedema (HAE) which causes swelling in the face, throat, hands, feet, gastrointestinal tract, genitals and face. 

Why take the test?

This test measures the levels of C1-INH and can be used to help diagnose HAE.

What's tested


How it works



Purchase your Kit

Just order a test online and get your kit delivered right to your door unless you are ordering a COVID-19 Fit to Fly test where you will be given appointment options to attend our clinics across the United Kingdom for a nose and throat swab PCR test at the checkout stage.



Take your test and post

Follow our simple instructions to take your sample and post back the enclosed prepaid envelope to our accredited lab for processing. We also offer home or workplace visits by a qualified nurse. For COVID-19 Fit to Fly tests you must attend one of our partner clinics for our trained collection officers to take your sample. You will then have the results emailed to you.



Get results directly to your dashboard

You will receive an email notification from our medical team when your results are available on your secure personalised health dashboard.