The Link Between Acute Liver Failure And Bariatric Surgery

I would reconsider taking any pain meds at this point.  "Do I REALLY need this?"

Occasional, low dose use of acetaminophen shouldn't put an otherwise healthy post-bariatric patient at risk. As a general rule of thumb, for adults, the max daily dose is 75 mg/kg/24 hrs up to 4gm/24 hrs, but that shouldn't be taken on a regular basis either.

APAP is not a benign drug. Many healthcare providers don't think it should be OTC, and I've gone back and forth with how I feel about it. Whatever the med, use the lowest dose possible to treat the problem. And bottom line, if you don't need it, don't take it. Those of us who are s/p WLS have to be especially careful of everything we put in our mouth, right?

Many studies have shown that oral medications are absorbed at different rates and amounts in bypass folks than in "regular" people. Most are absorbed at a faster rate but a lower amount. However, acetaminophen is absorbed by bypass patients at almost twice the efficiency as in normal folks. These absorption differences can pose a lot of problems since the guidelines for safe dosing come from studies in unaltered systems AND since so many drugs simply haven't been examined in bypass patients. I happened to just run across this paper (below) last night while doing some research to give to my Orthopedic surgeon to help him understand which meds and dosages to consider for my upcoming hip replacement. My major concerns were 1. Opioids seem to hit quickly and wear off almost as quickly and require MUCH higher doses than pre-op (they used to knock me flat out but post-op barely touch the pain-- unfortunately, despite all the anecdotal evidence that we absorb them differently, I have not found any studies investigating opioid absorption after bypass) and 2. oral Warfarin and Coumadin (blood thinners) don't work well for bypass patients so injectable thinners will need to be used. During my research, I was surprised to see that tylenol is absorbed at 100% higher efficiency in bypass folks. This scared the crap out of me since I have been taking narcotics with APAP quite a bit recently and was already concerned about my acetaminophen intake IF I absorbed it like a normal person. Yikes!

Anyway, the increased acetaminophen absorption rate and levels have been shown in multiple studies and we know alcohol is also metabolized differently in bypass patients so I am not surprised that studies are now seeking to tie increased risk of  liver failure to bypass. I am sure more investigations into other drugs would show many have the ability to contribute to the increased risk. 

This is a review of several studies and below is a part about acetaminophen absortion:

Drug Therapy-Related Issues
in Patients *****ceived
Bariatric Surgery by Chan 2010

 

Acetaminophen absorption
kinetics, a marker to estimate gastric emptying
rate, was performed in a study of patients who underwent
gastrectomy for malignancy. In these patients, an
esophageal jejunostomy was constructed using the
Roux-en-Y technique. The results showed that the rate
of acetaminophen absorption (administered as oral
powder, mixed with a liquid meal) was significantly
shortened in patients receiving this procedure, compared
with healthy subjects (14). This observation was
confirmed in our recently completed study in obese
patients *****ceived RYGB. Acetaminophen kinetics
were determined preoperatively, as well as 3 months
and 1 year after surgery. Acetaminophen was administered
as oral liquid. We found that the mean peak
acetaminophen concentration was nearly doubled (p < 0.01) following RYGB, and the mean time to peak
concentration was significantly shortened, from about
45 minutes to around 10 minutes in both postoperative
study visits (15).

 

14. Ueno T, Tanaka A, Hamanaka Y, et al. Serum drug concentrations
after oral administration of paracetamol to patients with surgical
resection of the gastrointestinal tract. Br J Clin Pharmacol.
1995;39(3):330-2.
15. Chan, L-N, Lin YS, Horn, JR, et al. The Effect of Proximal Rouxen-
Y Gastric Bypass Surgery on Upper Gastrointestinal Transit
Time: A Pilot Study. [Abstract]. J Parentr Ent Nutr (JPEN)
2010;34(2).

You can always have a blood level drawn if you were curious. But sounds like we need to stick to half as much as what would be recommended for non WLS patients, just to be safe. Good to know. I'm going to ask my surgeon what he thinks about this study when I see him next month.

Yes, I will certainly restrict my intake while I am navigating this hip replacement.

You may find that your surgeon has no idea about this study. There seems to be a huge disconnect between practicing bariatric surgeons and active researching surgeons. If your surgeon knows you are keeping up with the literature, it may provide the much needed impetus to get involved with the current literature again (if he is not already-- if he is, that's wonderful!).

He may know something about it. Or he may assign me to find out more, LOL!! He runs the program in Bariatrics at University of South Florida. They are actively involved in research and teaching, so he's pretty up on his stuff. His NP is also great about sharing what they are studying. 

Odd about the blood thinners... I have been on Coumadin almost continuously since 1979 and have been on the same dose for about 10 years.  My dose did not change after my RNY (although it is more subject to brief variations based on my food choices).

 

Lora

This doesn't surprise me at all.  It's known even amongst the non-WLS community that too much Tylenol will tax the liver.  Since we aren't allowed NSAIDS, Tylenol is what is usually recommended for common pains.  It's not meant to be taken long-term for anyone.

I am not worried about it for me I probably haven't taken more than 8-10 tylenol in the 7 years since surgery.  I have taken Alieve about 3 times (under doctors orders)......I just don't have many ailments that require medications (THANKFUL I AM).

I think when I pass - they'll do an autopsy and find a tumor filled with Tylenol, Splenda and anti-epileptic medications.

LOL Beth, now Splenda is a different story.  I'm sure I use way to much Splenda.