Log in
MPN Voice
3,493 members5,197 posts

Pegasys and Low Blood Counts

Hi Everyone,

Can Pegasys (Inteferon) lower your counts too much? I've been taking Pegasys for just over a year now, and as I look back over my results, apart from the odd blip, all my counts are steadily declining, and I'm wondering if this pattern will continue or will things 'plateau' out at some stage. As most of my counts are now either at the low end of the normal range or just below, I'm bit concerned that they may be get too low. Or am I 'borrowing trouble' that I don't need to?

Thanks for any thoughts/advice,


15 Replies

Hello Marie, , I've no experience of peg interferon so no help there but I'm sure our friends here have and will be able to help. . What I can tell you is that after my recent Stem Cell Transplant it never ceases to amaze me how ones body can function on the lowest of counts. I know it's different but even now my counts run something like Whites : 2.7 , Haemoglobin 90, Platelets 65, Neutrophil 2.06. . OK I had 2 bags reds last Friday coz they dropped tad too low and they don't like me anaemic. .

If you are worried about them you need to have a good chat with your Hem to agree your dosing of Peg is right coz you don't want any unnecessary transfusion etc. . .

Hope you keep 'well' . Chris


Thankyou Chris, wow those counts are very low! Do hope you are making a good recovery after your recent stem cell transplant.

I am not due to see my Haematologist till Feb, but have managed an appointment with one of the registrars next week, so will see how that goes.


Yeah that's a good move Marie, , give you some peace of mind I hope as a couple months is a longish time in our world. . .

I'm going along ok but it's mainly out of my control except to do as I'm advised and take drugs, stay away from crowded places, and take rest as and when I need it.

Good luck next week. . Cheers Chris



My wife is taking Pegysus Interferon and her platelets dropped from 685 to 193.

She is now on the minimum dose and only injecting once every three weeks. If it's still low on her next visit she will only need to inject once a month.

The only concern is if your white blood count gets too low but I am sure your haematologist will monitor this.

For my wife the interferon had been fantastic so far. Apart from a little hair loss she has had no side effects and life is generally good

1 like

Just wondering does your wife have ET or PV??.


Hi Mickey

My wife has PV with a bit of ET thrown in for good measure!


Hey LondonKid,

Thanks for your reply. That's wonderful your wife is doing so well. Is she taking any other meds or regular venesections?

I'm currently on the lowest dose too, injecting once a week, my platelets are at 196, so maybe I will be able to stretch out how often I inject too.

Had a mild heart attack last year, as platelets were at 1800, so interferon has been amazing in bringing everything down to where they should.

Be interesting to see what this registras has to say next week.


Hi Marie,

My wife's PV was picked up during a routine blood test for an unrelated ailment. Her platelet count was in the 450-500 range so she was referred to a haemotologist at a very early stage. Therefore she was has never had any clotting issue (touching wood for good luck!!!)

At first it was just fairly infrequent venesections and daily aspirins until her platelet count hit the 700 mark which was at the end of last year.

Since January 2015 she has been taking pegylated interferon and aspirin only and the venesections stopped altogether.

She has not been back to the hospital since my last message so she is still on one injection every three weeks and we're hoping this turns to once monthly.

It's all very strange at the moment as her platelet count seems to have almost stabilised and is not increasing even though her dosage is low.

It sounds like you're in a similar position to her

Have a great weekend

London kid


Hi Marie - I've just started on Pegasys and my haem has explained that as LondonKid has said, they will reduce dosage and frequency once my counts have dropped further - they have patients who are now just on 45mcg every 6 weeks, which will be great if I can get to that! They even envisage stopping treatment for a while and only starting if platelets begin to rise again. Hopefully your haem can advise if this sort of approach would work for you as we are all different of course..! Best of luck, Andy


Hi Andy are do you have ET or PV. I'm going to go see a specialist who only give angrylide or pegasy and I heard pegasy is recommended for ET?.


Sorry forgot to put the is NOT recommended for ET.


Hi Mickey - I have ET, CALR+ - my haem is getting good results with Pegasys for other ET patients and so far it's suiting me fine - time will tell how well it controls my counts...


Thanks Andy,

I didn't realise Peg could taken less frequently than weekly let alone stopped for periods of time, so that's good to be aware of.

Will chat with the Registra about this next week or my Haematologist in Feb when I see her next.


Marie, Peg has maintained my counts well however as others have pointed out neutropenia and sometimes Liver enzymes can be a problem requiring intermittent holidays from the drug which vary in length according to the individual. I had a couple of years off the drug and my counts remained stable.



That's great Keith,

A holiday from injecting sounds great! I wasn't super worried, but just noticed, that the counts seemed to be going steadily down, which is great when they had been so high, but wasn't sure what happens if they got too low.


You may also like...