Pharmacy Phriday #7: Bactrim Adverse Events

<p><strong>Contributor: Cheyenne Bean, PharmD</strong></p> <p><strong>Educational Pearls:</strong></p> <ul> <li style="font-weight: 400;" aria-level="1"><span style= "font-weight: 400;">Bactrim (TMP-SMX) is a sulfa antibiotic used for a number of infections but can have untoward effects.</span></li> <li style="font-weight: 400;" aria-level="1"><span style= "font-weight: 400;">Hypoglycemia can be induced by the sulfa component of Bactrim, which binds receptors in the pancreas causing insulin to be secreted, dropping blood sugar levels.</span></li> <li style="list-style: none; display: inline"> <ul> <li style="font-weight: 400;" aria-level="2"><span style= "font-weight: 400;">Oral diabetic medications, specifically sulfonylureas, when taken with Bactrim most often lead to these hypoglycemic episodes.</span></li> </ul> </li> <li style="font-weight: 400;" aria-level="1"><span style= "font-weight: 400;">Hyperkalemia can be induced by Trimethoprim by blocking potassium excretion in the kidney, so Bactrim in combination with ACE inhibitors/ARBs/spironolactone can induce high potassium.</span></li> <li style="font-weight: 400;" aria-level="1"><span style= "font-weight: 400;">When prescribing Bactrim, remember to check home medications and if a patient is taking an above medication, check a baseline BGL and potassium.</span></li> </ul> <p><strong>References</strong></p> <p><span style="font-weight: 400;">1)</span> <span style= "font-weight: 400;">Khorvash F, Moeinzadeh F, Saffaei A, Hakamifard A.</span> <a href= "https://pubmed.ncbi.nlm.nih.gov/31422395/"><span style= "font-weight: 400;">Trimethoprim-sulfamethoxazole Induced Hyponatremia and Hyperkalemia, The Necessity of Electrolyte Follow-up in Every Patient</span></a><span style= "font-weight: 400;">. Iran J Kidney Dis. 2019 Jul;13(4):277-280. PMID: 31422395.</span></p> <p><span style="font-weight: 400;">2)</span> <span style= "font-weight: 400;">Kennedy KE, Teng C, Patek TM, Frei CR.</span> <a href="https://pubmed.ncbi.nlm.nih.gov/31863282/"><span style= "font-weight: