James Bowen, MD – MS Center, Swedish Neuroscience Institute:
In NMO, the immune system is too active, so all of our treatments are really directed at decreasing the immune system to bring it back into balance. Because of this, they all have side effects. Some of the side effects are related directly to the suppression of the immune system and we have to make sure that we’re not overdoing it in that regard. Other side effects would be unique to each medication and may affect other organ systems like liver function for example. Because of this, each of the medications has monitoring that must be done. Sometimes of liver or other things. You should check with your doctor to see how frequently that needs to be performed. In addition, we need to monitor how much of an effect we’re having on the immune system to make sure that we’re not overdoing it and this usually requires a blood test to look at the immune cells in the blood. Again, check with your doctor to see how frequently that should be done, given the medication that you’re on.
Another thing to keep in mind is that when you go to the pharmacy, you’ll get a list of the side effects of your medication and it’s important to realize that not everything on that list is actually a true side effect of the medication. Things that are true side effects are listed on that list, but in addition there are a number of things on the list that may not actually be true. The reason for this is that when a study is done of a medication, they look at all the side effects that affect more than 2% of the population that participated in that study. And if there is something that happens to people that affects more than 2% and it’s even one patient more common in the treatment group compared to the placebo, then it goes on that list.
An example of this might be if you had a medication that there were 500 patients that had headaches in the placebo arm and 501 that were in the treatment arm, that would go on the list, even though 500 versus 501 is certainly not an indication that that would be a side effect. If you do have a side effect, even if it’s on the list, you should talk to your doctor to see how realistic it is that this would be something that would be expected from that medication so that decisions can be made about whether to continue or switch to something else.