Higher Ig

Also known as antibodies, they’re proteins made by your immune system to help fight infections like viruses and bacteria. In a nutshell, the Ig from donations like yours is the active ingredient in treatments given to people with weak immune systems or immune conditions. Your plasma helps them fight those infections.

We test all plasma donors to make sure every donor’s Ig levels are high enough for them to donate safely. Having normal Ig levels helps keep you healthy and well, so if it were low, it might mean taking a break from donating. And if it’s higher but still in the normal range? Well, that makes you a super donor.

We test all donors after their first donation, and then yearly after that. Just to keep an eye on it.

Okay, bear with us.

The IgG (that’s the main immunoglobulin that gives long term protection against infections) reference or normal range is 5 to 15 grams per litre (g/L). If a donor tests between 5-6 g/L we ask them to take a break from giving plasma, to keep them in that range. Lower than 5, and we’ll ask you not to give plasma at all.

If your levels are 9.5g/L to 15g/L, you have higher levels than most other people, but your Ig level is still within the normal range. And, our data shows you can donate more often than someone in the lower normal range. It’s like you have an extra reserve of Ig.

Yes, we’ll send you a letter. If it’s low or on the lower end of normal, we’ll let you know what it means for you and your donation frequency.

If it’s especially high, we’ll do some more testing to make sure there aren’t any other conditions that might cause abnormal protein production. Then we’ll reach out to let you know if your results are significantly high or we found an abnormality.

If your results are in the normal range but higher than average, we might send you an email to let you know you’re something of a super donor.

‘Normal’ ranges are just an average range across a healthy population. Some people have higher, some lower. But unless you’re really high (i.e. outside of the reference range), it’s still considered ‘normal’.

Your levels may take a little dip after donating plasma. We expect that, because your Ig is the super ingredient for plasma. That’s why we ask some people with low levels not to donate plasma, or to take a little break. But if your levels are already on the higher end of the range, it’s extremely unlikely for your levels to fall below normal or in the lower range. Even if you donate every two weeks.

But we check once a year anyway, so we’ll let you know if you should donate less frequently. For now, you should donate as often as you can to make the biggest difference.

If you want them, you can call us and ask for them. But they won’t give you an additional information relating to your health, especially if we’ve already provided you with the range you fall in (which we will if you have extra reserve).

Doctors only order these tests if there is a concern about repeated infections or other rare causes.

As you know, we check your haemoglobin and blood pressure before your donation. We also check your ferritin periodically if you donate whole blood and in certain circumstances for plasma donors. Ferritin lets us know what your iron stores are like. You can check those stats (or show them to your doctor) in the Lifeblood app.