Single fiber EMG

[jmbatgirl]

I'm having a colonoscopy two days prior to a single fiber EMG.  Can the drugs used for sedation during the colonoscopy, or any other medications for that matter, interfere with the results of the EMG?  The drugs for the colonoscopy will likely be Versed, Demerol, or anti-nausea medication.

Thank you.  

[Neuro Forum]

Thanks for using the forum. I am happy to address your questions, and my answer will be based on the information you provided here. Please make sure you recognize that this forum is for educational purposes only, and it does not substitute for a formal office visit with your doctor.

Few medications affect the results on an EMG, though some can. Demerol, versed, and other medications used in colonoscopy may have some effects in that they cause some sedation, perhaps interfering with your ability to participate in the parts of the EMG in which your participation is necessary. However in general, their effects are short-lived (hours) and would not be expected to continue causing sedation 2 days after your EMG. Other than that, it would be unlikely for them to affect the actual results of these tests. However, it would be best to contact the lab where the EMG is going to be conducted and make sure that they do not have a different opinion.

Thank you for using the forum, I hope you find this information useful, good luck.

[Heiferly]

I would think dehydration would effect an EMG, particularly if for example your potassium level was severely depleted.  Perhaps this could give a false positive for hypokalemic periodic paralysis?  Talk to your doctor about ways to keep your fluids and electrolytes in balance despite the prep for the colonoscopy?

[Fionajnz]

I cannot directly answer your question about the EMG, but I can tell you about the colonoscopy.  The main issue I had was related to dehydration, which landed me in the ER with low potassium two days after the colonoscopy.  If you have electrolyte probs, make sure they do bloodwork before and after the procedure.  

The meds used generally only stay in your system for up to 24hrs.  They actually have a pretty short half life and the procedure only takes on average 20 mins or so.  The prep is pretty foul tasting, so know that you can add crystal lite or sprite/7-up to make it taste better.  I used powdered gatorade in each 8oz I drank.....

Best wishes.

Fionajnz