Wednesday, January 18, 2012

Treating ME/CFS With Imunovir

In my post last week on immune system abnormalities in ME/CFS, I promised to follow-up with information on Imunovir, a prescription medication that has helped me improve over the past year.

Remember I explained that ME/CFS is neither an immune deficiency nor an auto-immune disease?  Parts of our immune systems are over-active and other parts are under-active.  This means that suppressing the immune system with steroids (as is often done with auto-immune diseases) won't work for us, and stimulating the entire immune system is likely to make us feel even worse.  What we need is an immune system modulator, something that will help re-balance our immune systems, restoring the normal Th1-Th2 balance that we are missing.

I learned this fairly early in my illness, but there didn't seem to be many options available for treatment.  I tried many herbal supplements over the years that were supposed to be immune system modulators (various types of mushroom blends, for instance), but I never noticed any improvement.  I learned about Imunovir years ago, but since it is not sold in the US, I thought it was unavailable to me (my primary care physician didn't feel comfortable prescribing something not available in the US).  Then, last year, my Infectious Disease/CFS doctor suggested trying Imunovir - I was thrilled to have a chance to try it after all these years!

It turns out it is fairly easy to get, if you know how.  Imunovir has been used safely in Europe and Canada for decades (it has not gone through the FDA process in the US for political reasons, not safety reasons).  My doctor gave me a prescription that I faxed to a pharmaceutical distributor in Canada.  Imunovir costs $100 for about a month's supply (dosing varies), and there is a $30 shipping fee, but my insurance covers Immunovir at 70% (I have to submit the receipts after I get it), and I can reduce the shipping fee by ordering several months' worth at a time.  A friend has told me there is a cheaper generic version (slightly different but similar), but I don't have any details on that.

Dosing of Imunovir is fairly complicated.  Apparently, immune system modulators work best by pulsing the dose; a steady dose stops working after a while.  I have read all sorts of complicated dosing schedules online, but my doctor suggested a schedule used by Dr. Nancy Klimas, a renowned CFS specialist and researcher: Start with 1 tablet (500 mg) twice a day for the first week, then go up to 2 tablets twice a day for 3 weeks, then increase to 3 tablets twice a day (6 total).  In all cases, take Imunovir Monday through Friday and take none at all on Saturday and Sunday.  I have read that Dr. Cheney (another renowned CFS doctor) also suggests changing the dose each week and taking it for 2 months, then taking an entire month off.

When I tried to go up to the maximum dose of 6 tablets a day, I had some side effects.  I found that taking 2-3 tablets late in the day left me overstimulated and unable to get to sleep.  I backed off to 4 per day, taking 2 in the morning and 2 in the afternoon, but then I had some mild immune symptoms (sore throat and aches) after going so long without any overnight and then taking 2 in the morning.  So, I have finally settled on my own dosing schedule:  1 with breakfast, 1 at mid-morning, 1 with lunch, 1 after my nap (weekends off), and it seems to be working well for me.  To mix it up, sometimes I take only 2 pills a day for a week.

As I explained in my earlier post on my improvement last year, I felt better overall last year, with improvements in energy, more good days, and fewer crash days.  Some of that improvement was due to beta blockers and some was due to Imunovir, and it's hard to completely separate the effects of the two for me.  Some signs that my immune system is functioning more normally include: fewer crashes, crashing less frequently when one of my kids is exposed to a virus, and a significant reduction in allergy symptoms.  I need to go back and quantify the allergy improvement, but it just occurred to me recently that a year ago, my allergies had ramped up significantly and now they are back to being mild.  Also, I typically feel the worst in the winter, when there are lots of viruses floating around causing me to crash, but I haven't seen that worsening this year.  I also believe the Imunovir has helped me to feel more energetic.  I feel more physically and mentally alert now and only have that no-energy, no-motivation, can't-think-clearly feeling on rare bad crash days.

I also believe that Imunovir may have helped me to finally get rid of the Lyme disease I've been fighting for the past three years.  With our reduced response to infections, people with CFS tend to have a very difficult time getting rid of Lyme disease and its co-infections completely.  I don't know for sure yet whether I am truly rid of Lyme (see my earlier post), but I am off my Lyme meds for the first time in years and so far, so good.

So, I plan to continue to take Immunovir and also want to try it for my son, Jamie, who - as most of you know - has been struggling horribly with his Lyme treatment this past year.

One way to quantitatively measure the health of our immune systems is by measuring Natural Killer Cell function, which is typically low in people with CFS, due to that Th1-Th2 imbalance.  I just realized I haven't had mine tested recently, so I will ask my doctor to check mine (which has been historically low) the next time I see her.

Once again, please remember that I am not a medical professional, and the information presented here is just a summary of my own experience and the understanding I have gained from reading research.  If I have made any technical mistakes here, please let me know, and, as always, talk to your own doctor about your own unique circumstances.

(NOTE: In an earlier version of this post, I had misspelled Imunovir as Immunovir.  I am including this note in the hopes that a search engine will still find this post, despite my mistake).


  1. Thanks for posting this Sue :-) I am glad it's been working for you!

  2. this is an excellent and highly informative post. i hope you will do more focusing on the science in the future.

  3. Hi, I stumbled upon your blog through Joanne's "Looking at Lyme Disease" Blog.

    What's the story behind Immunovir? Why is it a political issue to not be able to get it in the US?

    I've been thinking about something ever since I read the studies on rituximab on CFS/ME patients in Norway and wondered if that drug would help Lyme disease patients with persisting symptoms. Here you're taking Immunovir, and it seems to have similar effects as rituximab.

    What are the risks of taking it as you do? Side effects other than insomnia?

    I am wondering if it would help me and others. Why haven't they tried a clinical trial for this for CFS/ME patients? Or has someone, and I just hadn't read about it?

    Thank you for sharing your story. I hope you and your son steadily improve.

  4. Camp Other -

    I don't know the story behind why Immunovir has not been officially approved by the FDA - I don't generally pay much attention to those types of political issues because I have very limited energy and I'd rather focus on healing. It doesn't really matter since it can be easily (and legally) obtained through non-US sources.

    Rituximab is an entirely different drug, a chemotherapy drug that attacks part of the immune system and has significant side effects and risks. I am looking forward to more follow-up research on Rituximab, but I wouldn't lump it into the same category as Immunovir.

    I've experienced only very mild side effects with Immunovir, as explained in this post, and they were easily addressed simply by adjusting my dose. I don't believe there are any hazards or risks associated with it.

    There have been some limited research studies on Immunovir in people with ME/CFS, but like all CFS research, it has been limited by a lack of funding. This link includes mention of an Immunovir trial (note that this article is from 2001, so some of the information is a bit outdated):

    Here's a brief article on using Immunovir for CFS. It references studies but not specifically (note isoprinosine is the generic term for the brand name Immunovir):

    Here's another brief article that summarizes research on Immunovir for CFS:

    Hope that helps answer some of your questions.


  5. That's awesome to have found something that helps and be able to come off of (Lyme) meds! I'm so happy for you and wish you continued success with them!

  6. Anonymous3:14 PM

    Fantastic Sue!
    I literally forwarded this to my doctor, as I've really, really been considering Immunovir as of late! Thank you for your wonderfully articulate and humanly-written experience and explanation!

    So thrilled it's helping you (and the boys).

    Answering the "politics" question…it's ALL about money and marketability/patenting. As long as we can get it; we're fortunate.

    Are you also still on LDN?


  7. Hi, Martine -

    Thanks for the kind words - I'm glad this was helpful to you!

    Yes, I am still on LDN, and my 17 yo takes it now, too. Thanks for asking - I meant to mention it here because LDN also helps to normalize the immune system, though in a different way.


  8. good info! thx! I like how you worked out the dosing schedule to fit your needs. My dr said that Immunovir was just another way to work on the virus (I have epstein-Barr) but it sounds like that maynot be the case. I am glad to have another possibility to explore!

  9. Well, Karen, your doctor is not necessarily wrong; I think it's just a slightly different way of looking at things. From what I've read, Immunovir is mainly used in Europe against viruses. It's not attacking viruses directly, like an anti-viral med, but is doing a similar job in a different way by helping to improve the immune system so it can fight the viruses itself. In fact, there are lots of healthy people with EBV (some experts say over 90% of the adult population has been exposed to EBV), but it doesn't have any effect of them. The only reason EBV is a factor for people with CFS is because our immune systems aren't working properly.

    Hope it helps you - let me know how it goes!


  10. Sue,

    Thank you for giving me more information on Immunovir, including its side effects and links to research. I didn't intend to lump Immunovir in with rituximab in terms of them being the same kind of drug with the same mechanism - only that they seem to have similar effects on improving fatigue.

    Best wishes for your continued healing,


  11. Anonymous1:12 AM


    Do you see a CFS specialist or are you able to get these kinds of treatments from a regular doctor?

    1. My family doctor understands and treats CFS, so many of my treatments (for sleep dysfunction, for OI, etc.) come from her, but she didn't feel comfortable prescribing Immunovir from Canada.

      So, for the more specialized treatments like Immunovir, I see Dr. Susan Levine, an Infectious Disease doc in NYC who specializes in CFS.


  12. Anonymous2:36 PM

    I get extremely worse fatigue while on Imunovir. I did enjoy my month off in December and felt improved after the 6 month regimen. But it was not a walk in the park. Its alot of work - at least it is for me, makes me much worse while on it. i can't think, can hardly keep eyes open. I also have low killer cell function and have had chronic ebv due to such.

    1. Wow, that's interesting that you got worse on Imunovir. odd because it has the opposite effect on me - it GIVES me energy. Did you try different doses? I do well on 4 pills a day, but 6 a day was too much for me.

      Have you tried low-dose naltrexone? Also helps the immune system and very good for bringing up low NK cell count.


  13. Anonymous1:50 PM

    Hi Sue,

    I just came across your blog and found it very helpful! I have had cfs for 26 years and my worst issue issue is chronic swelling and pain my lymph nodes and glands and muscle pain. Did you find that Imunovir helped with that? I am going to show this article to my doctor,


    1. The symptoms you're describing are typically caused mainly by immune system dysfunction, so Imunovir should help. It can take a bit of trial and error to find the right dose for yourself.

      Good luck!


  14. Anonymous2:36 PM

    I've had CFS for 20 years and was treated by Dr Lerner (CFS clinic in Beverly Hills, MI) for 3 years with heavy doses of Valtrex (6 grams/day) and Valcyte (4 - 450mg pills/day). He has an energy index scale that put me at 4 with goal of 7.5 in 10 months. After 2 years I got to 6.5 and after 3 years still at 6.5. My primary care Dr advised me to stop the antivirals and said he doubted they would come back, so I tapered off the antivirals and within 3 months I crashed back to 4. I just started seeing a colleague of Dr Klimas (mentioned in your Jan 2012 blog) and they are starting me on low dose Naltrexone and Imunovir, as well as putting me back on the Valtrex/valcyte 3 pills each/day. So I believe the experts in the CFS field are prescribing exactly what you are recommending. I'll update you after I reach the maximum dosing level which will take 12 weeks.

    1. Thanks for sharing your story! Dr. Lerner is an excellent doctor - glad he was able to help you. I hope the LDN and Imunovir and antivirals work for you.

      Here are some additional details of what experience has taught us on dosing of Imunovir which is very important. Also, I don;t know the current status of Imunovir but it was on long-term backorder for a long time, and we had to switch to generic inosine - sold in the US as a supplement, much cheaper than Imunovir - we saw no difference between the two at all so have stuck with the inexpensive version.

      I plan to also write a new post next week on dosing of LDN, so stay tuned!