Medications and Malabsorption
I had Roux-en-Y in Nov 2004 (140lbs ago) and feeling great. No regrets, no complications, loving life. However I just had a long course of antibiotics and came up with an allergic reaction. My docs prescribed prednisone and benadryl (pills) and I got no relief. I ended up in the ER for iv meds and they worked great. I can't find any studies or information about malabsorption for these meds. They sent me home with a liquid version of the meds and I continue to get better. Has anyone had this same experience with meds? Should I always ask for the liquid equivalent? The antibiotics seemed to work, cured the infection...I appreciate that this place exists and that you all are here. 
Below is a post that I've saved b/c it answers some of the same questions you've asked. Glad to hear the liquid antibiotics are helping & hope you continue to improve.
Vickie J.
RE: Medical treatment after wls?
Response from Karyn B at 5:50 AM PST on 01/08/2007
Chicago, IL - RNY (06/18/2003)
I think absorption is still an individual thing, but I have been seeing more about this. Here's an article written by a pharmacist who has had gastric bypass surgery himself (printed with his permission).
---------------------------------
Medications and the Gastric Bypass Patient
by Michael McEvoy Pharm.D.
As a medication travels through the body, it undergoes four* distinct phases:
? Absorption
? Distribution
? Metabolism * Not all drugs are metabolized, some are excreted unchanged
? Excretion
Patients with liver disease may have problems metabolizing medications; patients with kidney disease may have problems excreting drugs. Gastric bypass patients will have a variable absorption of medications, based on the chemical characteristics of the medication and on the physical properties of the dosage form (meaning: "the finished product" -- tablet, capsule, etc.) containing the active ingredient.
First a chemistry lesson (it won't be too painful). Medications, like all chemicals can exist to two states: ionized and un-ionized. When you dissolve a teaspoonful of table salt in a glass of water, the sodium ions (represented by the chemical symbol Na+) separate from the chloride ions (represented by the chemical symbol Cl-). The Na+ and CI- are said to be 'ionized.'
When you dissolve a teaspoon of sugar in a glass of water, no separation into electrically charged particles takes place. The sugar is in an un-ionized state. Salt and sugar serve as examples of what happens to medications.
Medications are best absorbed by our bodies in the un-ionized state. Most medications can be described as the salts of weak acids or weak bases. By 'salt' we mean that one chemical combines with another chemical to make a new compound. The salt of a weak base and a strong acid, such as ranitidine HCI (Zantac ®) is un-ionized in the presence of a stronger base (like small intestine juices.) The salt of a weak acid and a strong base, such as sodium phenobarbital (Luminal ®) is un-ionized in the presence of a stronger acid (like stomach juices.)
The small intestines are bathed in secretions which are basic (meaning alkaline, not acidic), so drugs that are salts of weak bases are best absorbed there. Gastric bypass patients should have no trouble absorbing these types of medications.
A clue to whether a medication is the salt of a weak acid or base can be found in the generic name. Medications that are "sodium something", "potassium something", "calcium- or magnesium something" are salts of weak acids.
Medications that are something-HCI (hydrogen chloride) or something-HBr (hydrogen bromide) are salts of weak bases.
The "sodium or potassium-something" drugs present the most problems with absorption. They are best absorbed in the presence of stomach acid, which is in very short supply on our pouches. There will be some absorption in the ionized state in our small intestines. Fortunately, our small intestines are VERY LONG and have a large surface area to absorb the medication. Medications are absorbed in the small intestines by passive non-ionic diffusion. Think of the intestinal wall like a sponge that picks up the medication and transports it from one edge of the sponge to the other, delivering it to the bloodstream. The rate and extent of absorption in passive non-ionic diffusion will be erratic and may vary from one Gastric Bypass patient to another.
A recent report in the April 27th 2006 issue of the New England Journal of Medicine again shows the importance of stomach acid in the absorption of certain medications. Patients who were on proton pump inhibitors (medications such as Prilosec ® (omeprazole) , Nexium ®, Protonix ®, and Prevacid ®) as part of the treatment of the ulcer causing bacteria Helicobacter pylori were found to have mal-absorption of the thyroid drug thyroxine sodium (Synthroid ®).
The study stated "patients with impaired acid secretion require an increased dose of thyroxine, suggesting that normal gastric acid secretion is necessary for the effective absorption of oral thyroxine."5
Many patients who have had gastric bypass surgery also have other medical problems which require medication for their treatment. In the May-June 2005 issue of Psychosomatics, a study was published which looked at the dissolution of common psychiatric medications in a Roux-en-Y gastric bypass model. It found that ten of twenty two psychiatric medication preparations had significantly less dissolution and two of twenty two medications had significantly greater dissolution in the post-RYGB environment, as compared with a control group. The medications were crushed in this study, which differs from clinical practice and that may account for the greater dissolution of the two medications. This study made no attempt to determine differences in absorbtion, however. Further study into the effects of RYGB surgery on serum blood levels is required.6
Some guidelines for your physician came from a review of this and other recent studies. Immediate release medications are preferred over time release medications. Monitor the levels of medications in the blood, if such monitoring exists (not all drugs can be monitored in this way). For drugs with a small volume of distribution (Vd) [this will mean something to your doctor, as a patient you need not worry about what this means], a lower maintenance dose may be required because of a decreased glomerular filtration rate which follows marked weight loss. Drugs such as lithium carbonate, valproic acid and oxcarbazine are common psychiatric medications with small Vd.7
The good news is that most patients after RYGB surgery require fewer medications, or at least reduced dosages of medications then they needed prior to the surgery.8
Other considerations: Enteric coated tablets are designed to pass through the stomach acid intact and be dissolved in the small intestines. They should present no problem to the Gastric Bypass patient. Controlled release dosage forms, however, may have erratic absorption as many (but not all) controlled release dosage forms depend on stomach acid to dissolve the coatings of the "tiny time pills". Suggest that your doctor prescribe immediate release preparations, even though this may mean that you have to take the medication multiple times a day instead of only once or twice a day.
Medications that require stomach acid for activation are another matter. The ulcer medication sucralfate (Carafate ®) (which I hope none of you will need!) requires stomach acid to attach itself as a protective coating over the ulcer. More important to us is calcium carbonate. Calcium is largely absorbed from the duodenum by an active transport system, which is bypassed during Roux-En-Y surgery. Calcium carbonate (Tums®) is frequently recommended for calcium supplementation because it contains a higher percentage of calcium than other calcium salts. But Calcium carbonate is a less soluble salt, which requires stomach acid to get into solution, which makes it absorbable. Ionized or unionized, the medication must be in solution to be of any use to you: if it is not in solution, it does you no good.
Gastric bypass patients should take a more soluble form of calcium, such as calcium citrate (Citracal ®), or better yet, get your calcium from your diet (Got cheese?)
Do not forget to take your vitamins. Because of impaired absorption, you should be taking at least two times the RDA of most vitamins. Don't worry about the water soluble vitamins; you body will discard those in excess of your body's need. You may find that the excess riboflavin colors your urine a bright yellow; this is normal. Fat soluble vitamins (A, D, E, and K) can accumulate if taken in great excess, but this will not be a problem, unless you take large doses. And these fat soluble vitamins are important. There can be visual problems in post RYGB patients who do not get enough vitamin A, such as dryness of the conjunctiva and cornea. The condition can even progress to night blindness with severe vitamin A deficiency.9
Roux-En-Y patients should get at least 7000 - 10,000 international units (IU) of vitamin A daily, 400 - 800 IU of vitamin D daily, and 400 - 800 IU of vitamin E daily. For duodenal switch patients, whose absorption is even more impaired, the recommendations are 1 ½ times the recommendations for RNY patients. Lap band patient do not suffer from malabsorbtion, but should consider supplementation at least to the recommended Daily Value, as indicated on the package label as 100% DV.
Dosages of vitamin A greater than 10,000 - 15,000 IU of vitamin A can result in adverse affects to the liver, skin, hair, and can cause visual changes. Pregnant females should consult their obstetrician for guidance, as high intake of vitamin A can have risks to the fetus.11
Calcification of soft tissue or hypercalcemia can occur with vitamin D intake > 2000 IU per day.
Doses of vitamin E up to 1000 IU per day are commonly prescribed in Alzheimer's patients, yet some gastrointestinal (GI) effects can occur, along with blood thinning" anti-platlet effects with daily intakes of greater than 800 IU per day.
The %DV for vitamin K is approximately 75 mcg. Patients who are taking the blood thinner Coumadin ® (warfarin sodium) should only take vitamin K supplements as advised by your physician, as vitamin K opposes the effects of Coumadin®; indeed vitamin K is given as an "antidote" to patients whose blood has been overly thinned with Coumadin®.
So take your vitamins! But don't over do the ADEKs.
Vitamin B12 (cyanocobalamin) requires both stomach acid and a substance secreted by the stomach called "intrinsic factor" for absorption via the oral route. You should be using a sublingual ('under the tongue") tablet or spray as your B12 supplement, as this bypasses the absorption problem altogether.
Iron, like calcium, is largely absorbed in the duodenum. Like calcium carbonate, ferrous sulfate is frequently recommended for iron supplementation because it contains a higher percentage of iron than other iron salts. Also like calcium carbonate, ferrous sulfate is a less soluble salt, which requires stomach acid to get into solution.
Gastric bypass patients should take a more soluble form of iron, such as ferrous fumarate (Ferro Sequels ®, Femiron ®), ferrous gluconate (Fergon ®), or a polysaccharide iron complex (Niferex ®). Remember to separate your calcium and iron supplement by at least two hours.
Some references for you and your doctor:
1. MacGregor AMC, Boggs L. Drug Distribution in Obesity and following
Bariatric Surgery: A literature review. Obes Surg 6:17-27, 1996
2. Chaymol G. Clinical pharmacokinetics of drugs in obesity. Clin
Pharmacokinet 25.103-114, 1993
3. Malone M. Altered Drug Disposition in Obesity and After Bariatric Surgery Nutr in Clin Practice 18:131-135, 2003
4. Fussy S. The skinny on gastric bypass: What pharmacists need to know US Pharmacist 30: HS-3-HS-12, 2005
5. Centanni, et al Thyroxine in Goiter, Helicobacter pylori Infection, and Chronic Gastritis. N Engl J Med. 2006;354:1787-95
6. Seaman, JS, et al Dissolution of Common Psychiatric Medications in a Roux-en-Y Gastric Bypass Model, Psychomatics 46:3, May-June 2005
7. McAlpine DE Current Psychiatry Vol 5 No 1, Jan 2006
8. Malone M and Alger-Mayer SA Medication Use Patterns after Gastric Bypass Surgery for Weight Management, Ann of Pharmacotherapy 39:637-42 April 2005
9. Lee WB et al Ocular Complications of Hypovitaminosis A after Bariatric Surgery J Optha 2005;112:1031-34
10. Evanston Northwestern Healthcare Bariatric Services. Long-term vitamin supplementation. June 2004
11. J. Canadian Med Assoc Vol 169 (1), 8 July 2003
I have found there were certain supplements and things I wasn't absorbing - one of them being my hormone. (I was passing it in the exact same size and shape as I took it in) so I've started cutting it up into quarters and don't seem to be having any trouble with it now. The only other thing I was having trouble with that way was green tea extract in capsules, so I just stopped taking them.
Hi Alice ... the pharmacist who wrote that article has led a few of the support group meetings I've been to, and we've discussed antibiotics ... one of the particular ones that we tend to malabsorb is Augmenten (I can vouch for that) ... and many have problems with a lot of the antibiotics. Mike mentions that with vitamins (not necessarily meds), gastric bypass post-ops should be taking 2X the recommended daily allowance, and duodenal switch post-ops should be taking 3X the recommended daily allowance.
He does update that paper from time to time (as more information becomes available), I'll be sure to post updates when I get them.
Karyn
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