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Lomotil oral

Solid Oral Potassium Tablets/Anticholinergics

This information is generalized and not intended as specific medical advice. Consult your healthcare professional before taking or discontinuing any drug or commencing any course of treatment.

Medical warning:

Serious. These medicines may interact and cause very harmful effects. Contact your healthcare professional (e.g. doctor or pharmacist) for more information.

How the interaction occurs:

Anticholinergic medicines slow down your gastrointestinal (GI) tract. Your potassium may remain in your stomach and/or intestine too long.

What might happen:

If your potassium medicine stays in your stomach and/or intestine too long, it may cause an ulcer.

What you should do about this interaction:

Let your healthcare professionals (e.g. doctor or pharmacist) know right away that you are taking these medicines together. Your doctor may change your potassium medicine while you are taking an anticholinergic medicine.To decrease your risk for stomach problems, take your potassium after meals with a large glass of water or other liquid. Let your doctor know right away if you have any severe vomiting, stomach pain, abdominal bloating, vomit that looks like coffee grounds or contains blood, and/or black or bloody stools.Your healthcare professionals may already be aware of this interaction and may be monitoring you for it. Do not start, stop, or change the dosage of any medicine before checking with them first.


1.K-Dur (potassium chloride) Canadian prescribing information. Merck Canada Inc. March, 2011.
2.K-TAB (potassium chloride) tablet, film coated, extended release, US Prescribing Information. Zydus Pharmaceuticals November, 2010.
3.K-Dur (potassium chloride) US prescribing information. Key Pharmaceuticals, Inc. April, 2004.
4.Potassium chloride extended-release capsules US Prescribing information. Ethex Corporation September, 2003.
5.Klor-Con (potassium chloride) US prescribing information. Upsher-Smith Laboratories 01/05.
6.Urocit-K (potassium citrate) US prescribing information. Mission Pharmacal December, 2009.
7.Slow-K (potassium chloride) US prescribing information. Novartis Pharmaceuticals Corporation April 2004.
8.Micro-K (potassium chloride) US prescribing information. KV Pharmaceutical 10/00.
9.Micro-K Extencaps (potassium chloride) Canadian prescribing information. Wyeth Pharmaceuticals 2007.
10.Slow-K (potassium chloride) Canadian prescribing information. Novartis Pharmaceuticals Canada Inc. 2007.
11.McMahon FG, Ryan JR, Akdamar K, Ertan A. Effect of potassium chloride supplements on upper gastrointestinal mucosa. Clin Pharmacol Ther 1984 Jun;35(6):852-5.
12.Kendall C, Krantz KD, Berger A, Sharp T. Endoscopic evaluation of slow-release potassium chloride preparations. Clin Pharmacol Ther 1985 Jul;38(1):28-30.
13.Gonzalez GB, Pak CY, Adams-Huet B, Taylor R, Bilhartz LE. Effect of potassium-magnesium citrate on upper gastrointestinal mucosa. Aliment Pharmacol Ther 1998 Jan;12(1):105-10.
14.Sinar DR, Bozymski EM, Blackshear JL. Effects of oral potassium supplements on upper gastrointestinal mucosa: multicenter clinical comparison of three formulations and placebo. Clin Ther 1986;8(2):157-63.
15.McMahon FG, Ryan JR, Akdamar K, Ertan A. Upper gastrointestinal lesions after potassium chloride supplements: a controlled clinical trial. Lancet 1982 Nov 13;2(8307):1059-61.
16.Barkin JS, Harary AM, Shamblen CE, Lasseter KC. Potassium chloride and gastrointestinal injury. Ann Intern Med 1983 Feb;98(2):261-2.
17.Strom BL, Carson JL, Schinnar R, Sim E, Maislin G, Soper K, Morse ML. Upper gastrointestinal tract bleeding from oral potassium chloride. Comparative risk from microencapsulated vs wax-matrix formulations. Arch Intern Med 1987 May;147(5):954-7.
18.Rosenthal T, Adar R, Militianu J, Deutsch V. Esophageal ulceration and oral potassium chloride ingestion. Chest 1974 Apr;65(4):463-5.
19.McLoughlin JC. Effects on upper gastrointestinal mucosa of three delivery systems of potassium as supplement to frusemide administration. J R Soc Med 1985 Jun;78(6):459-62.
20.Farquharson-Roberts MA, Giddings AE, Nunn AJ. Perforation of small bowel due to slow release potassium chloride (slow-K). Br Med J 1975 Jul 26; 3(5977):206.
21.O'Neill JL, Remington TL. Drug-induced esophageal injuries and dysphagia. Ann Pharmacother 2003 Nov;37(11):1675-84.

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