Health condition
CVID immunoglobulin therapy
Immunoglobulin replacement is the foundation of CVID treatment - donated antibody given intravenously every few weeks or subcutaneously at home every week - transforming infection rates and protecting lungs when dosed and monitored properly.
Why trust this guide
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Editorial team
Written by our editorial team from the UK sources listed on each page.
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Sourced from guidance
Checked against current NHS and UK specialist society guidance at the time of review.
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Current for 2026
Reviewed on 2026-09-27 with the next review scheduled for 2027-09-27.
Key facts
The essentials at a glance.
The symptoms to recognise, when to seek help, which specialist to see, and what treatment usually involves.
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Two routes: intravenous (IVIg) every 3-4 weeks in a day unit, or subcutaneous (SCIg) self-administered weekly at home - efficacy is equivalent, lifestyle differs
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Dosing targets trough IgG levels that keep YOU infection-free - the right level is individual, not just 'within range'
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Breakthrough infections despite therapy warrant dose review, not resignation
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It replaces IgG only: it does not correct IgA deficiency or T-cell problems, and live vaccine rules still apply
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Home therapy training, funding and supply are organised through NHS immunology centres; treatment is lifelong
Understanding the condition
What it is and what happens next.
What causes it, how it is diagnosed, and the treatment routes available in the UK.
What it is and how it feels
Immunoglobulin is a pooled gift from thousands of plasma donors - a broad library of antibodies standing in for the ones a CVID immune system cannot make. Given regularly it prevents rather than treats: pneumonia rates fall severalfold, hospital admissions drop, and the slow march of bronchiectasis can be halted. The practical choice between hospital infusions and weekly home subcutaneous injections is genuinely personal - veins, diaries, needle tolerance and travel all weigh in, and switching between routes is routine.
Diagnosis and treatment routes
Good therapy is actively managed: trough IgG measured and titrated upward if infections persist (higher troughs protect lungs better), annual review of infection diaries, lung function and CT where indicated, and prompt dose adjustment around weight change or protein loss. Side effects are usually minor - headache, fatigue around infusions - with rare reactions screened for. Anyone on replacement who still gets frequent infections should push for review; a private immunology consultation is typically available within about two weeks.
Seeing a specialist
Who to see, and how quickly you can be seen.
The specialist for this condition is usually a consultant clinical immunologist. Your GP can refer you on the NHS, or you can arrange a private consultation directly.
A quiet reminder
This guide is for information, not medical advice.
Your GP knows your history and can tell you which parts apply to you. If in doubt, see them - and seek urgent care for any of the emergency symptoms described above.
Frequently asked
Common questions about CVID immunoglobulin therapy.
Quick, plain-English answers to what people ask us most.
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What is immunoglobulin therapy for CVID?
Immunoglobulin replacement therapy is the foundation of CVID treatment - donated antibody given regularly, either intravenously every few weeks or subcutaneously more frequently, to restore protective antibody levels and reduce infection risk.
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Why is immunoglobulin therapy needed in CVID?
People with CVID don't produce enough of their own protective antibodies, leaving them vulnerable to recurrent infections. Immunoglobulin therapy replaces these missing antibodies, sourced from thousands of blood donors, to restore adequate protection.
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How is immunoglobulin therapy given?
It can be given intravenously (IVIG), typically every three to four weeks in a clinic setting, or subcutaneously (SCIG), often self-administered more frequently at home - the choice depends on individual preference and clinical factors.
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Is immunoglobulin therapy safe?
Yes, it's a well-established treatment with a good safety record, though some people experience mild side effects such as headache or fatigue, particularly with intravenous administration, which can often be managed by adjusting the infusion rate or premedication.
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How effective is immunoglobulin therapy at preventing infections?
It significantly reduces the frequency and severity of infections for most patients with CVID, though it doesn't eliminate infection risk entirely, so prompt treatment of any infections that do occur remains important.
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How long does someone need immunoglobulin therapy?
Treatment is typically lifelong for CVID, since the underlying antibody deficiency doesn't resolve, though the specific dose and frequency may be adjusted over time based on infection frequency and antibody trough levels.
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IVIG vs subcutaneous immunoglobulin - which is better?
Both are effective at raising antibody levels; IVIG involves less frequent but longer clinic-based infusions, while subcutaneous immunoglobulin allows more frequent, often self-administered dosing at home with more stable antibody levels between doses. The choice often comes down to individual preference and lifestyle.
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What happens if immunoglobulin doses are missed?
Missing doses can allow antibody levels to fall, increasing infection risk, which is why consistent adherence to the prescribed schedule is important, and any missed doses should be discussed with your immunology team.
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Does immunoglobulin therapy address the underlying cause of CVID?
No, it treats the consequence (low antibody levels) rather than curing the underlying immune defect, but for most patients it very effectively controls the main clinical problem - recurrent infections.
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When should I discuss immunoglobulin therapy with a specialist?
This should be discussed with an immunologist once a diagnosis of CVID (or another significant antibody deficiency) is confirmed. A private immunology consultation to review treatment options is often available within about two weeks.