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A-Cillin oral

Anticoagulants/Selected Penicillins

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:

Moderate. These medicines may cause some risk when taken together. Contact your healthcare professional (e.g. doctor or pharmacist) for more information.

How the interaction occurs:

The cause of the interaction is not known.

What might happen:

Amoxicillin or large doses of injectable penicillin may cause an increased chance of bleeding including bleeding from your gums, nosebleeds, unusual bruising, or dark stools.

What you should do about this interaction:

Contact your healthcare professional (e.g. doctor or pharmacist) about taking these two medicines together. If your doctor prescribes these medicines together, you may need to check your bleeding times more often. Patients with kidney failure may be more likely to experience this interaction, so let your doctor know if you have kidney problems.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.

References:

1.Brown CH 3rd, Natelson EA, Bradshaw W, Williams TW Jr, Alfrey CP Jr. The hemostatic defect produced by carbenicillin. N Engl J Med 1974 Aug 8; 291(6):265-70.
2.Brown CH 3rd, Natelson EA, Bradshaw MW, Alfrey C P Jr, Williams TW Jr. Study of the effects of ticarcillin on blood coagulation and platelet function. Antimicrob Agents Chemother 1975 May;7(5):652-7.
3.Brown CH 3rd, Bradshaw MJ, Natelson EA, Alfrey CP Jr, Williams TW Jr. Defective platelet function following the administration of penicillin compounds. Blood 1976 Jun;47(6):949-56.
4.Andrassy K, Ritz E, Hasper B, Scherz M, Walter E, Storch H. Penicillin-induced coagulation disorder. Lancet 1976 Nov 13; 2(7994):1039-41.
5.Dijkmans BA, Van Der Meer JW, Boekhout-Mussert MJ, Zaal-De Jong M, Mattie H. Prolonged bleeding time during azlocillin therapy. J Antimicrob Chemother 1980 Jul;6(4):554-6.
6.Gentry LO, Jemsek JG, Natelson EA. Effects of sodium piperacillin on platelet function in normal volunteers. Antimicrob Agents Chemother 1981 Apr;19(4):532-3.
7.Alexander DP, Russo ME, Fohrman DE, Rothstein G. Nafcillin-induced platelet dysfunction and bleeding. Antimicrob Agents Chemother 1983 Jan; 23(1):59-62.
8.Delavenne X, Laporte S, Demasles S, Mallouk N, Basset T, Tod M, Girard P, Mismetti P. Investigation of PK-PD drug-drug interaction between acenocoumarol and amoxicillin plus clavulanic acid. Fundam Clin Pharmacol 2009 Feb;23(1):127-35.
9.Kelly M, Moran J, Byrne S. Formation of rectus sheath hematoma with antibiotic use and warfarin therapy: a case report. Am J Geriatr Pharmacother 2005 Dec;3(4):266-9.
10.Davydov L, Yermolnik M, Cuni LJ. Warfarin and amoxicillin/clavulanate drug interaction. Ann Pharmacother 2003 Mar;37(3):367-70.
11.Penning-van Beest FJ, van Meegen E, Rosendaal FR, Stricker BH. Drug interactions as a cause of overanticoagulation on phenprocoumon or acenocoumarol predominantly concern antibacterial drugs. Clin Pharmacol Ther 2001 Jun;69(6):451-7.
12.Bandrowsky T, Vorono AA, Borris TJ, Marcantoni HW. Amoxicillin-related postextraction bleeding in an anticoagulated patient with tranexamic acid rinses. Oral Surg Oral Med Oral Pathol Oral Radiol Endod 1996 Dec; 82(6):610-2.
13.Tung JY, Johnson JL, Liacouras CA. Portal-mesenteric pylephlebitis with hepatic abscesses in a patient with Crohn's disease treated successfully with anticoagulation and antibiotics. J Pediatr Gastroenterol Nutr 1996 Nov;23(4):474-8.
14.Soto J, Sacristan JA, Alsar MJ, Fernandez-Viadero C, Verduga R. Probable acenocoumarol-amoxycillin interaction. Acta Haematol 1993;90(4):195-7.
15.Penning-van Beest FJ, Koerselman J, Herings RM. Risk of major bleeding during concomitant use of antibiotic drugs and coumarin anticoagulants. J Thromb Haemost 2008 Feb;6(2):284-90.
16.Zhang Q, Simoneau G, Verstuyft C, Drouet L, Bal dit Sollier C, Alvarez JC, Rizzo-Padoin N, Bergmann JF, Becquemont L, Mouly S. Amoxicillin/clavulanic acid-warfarin drug interaction: a randomized controlled trial. Br J Clin Pharmacol 2011 Feb;71(2):232-6.

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