I see that Cyrex testing will be inaccurate when a patient is taking steroids, and SIBO testing will be inaccurate with antibiotic use. How long should a patient be off these medications before testing?

A Cyrex panel is going to be inaccurate when someone’s taking steroids because steroids suppress the immune system, so you’re not going to have high levels of immunoglobulins, and the Cyrex [tests] are looking at immunoglobulin levels. What I normally do is I kind of get a sense, like, is the patient taking oral steroids or are these just topical for skin issues? Is this, like, an inhaled steroid? Because certainly, the degree to which you see that immune suppression is going to depend on the route of administration, the dose, etc. Sometimes, with the inhaled nasal steroids for seasonal allergies or the topical for skin lesions, eczema, [or] whatever it may be, it may not be that significant of an impact. What you do is you just order an immunoglobulin panel through LabCorp or Quest, so you look [at] what are the IgG levels, IgA, [and] IgM, and if those levels are at least above the lower 30 percent, you want to, kind of, be in the upper half, ideally, particularly for IgG and IgA, since that’s what we’re testing on Cyrex, then you’re okay to do that.

If somebody is on a high dose of oral steroids, then I’m probably going to let them finish the course, and then maybe after four weeks, I’m going to run that immunoglobulin panel because everyone’s going to have a different recovery time. I can’t give you just a clear, like, “this dose of steroid [for] this amount of time until their immune systems are ready to go.” You kind of just have to check and see what their immunoglobulin levels look like and are they adequate that we would expect to see them mounting an immune response to gluten or to the food sensitivities.

In terms of SIBO, right now, we do about four weeks after taking either prescription antibiotics or even botanical antimicrobials, so that one [is] not as clear. We’ve done two weeks after sometimes, but I think if you want it most accurate, probably about four weeks.