Drug Interactions between Lasix and sodium zirconium cyclosilicate

ADJUST DOSING INTERVAL: Because sodium zirconium cyclosilicate can transiently increase gastric pH, it may affect the absorption of coadministered medications that exhibit pH-dependent solubility. Altered efficacy or safety of these medications may occur when they are administered too close to the dosing of sodium zirconium cyclosilicate. According to the product labeling, 39 drugs were tested to determine potential interactions with sodium zirconium cyclosilicate. Drugs that did not show an in vitro interaction with sodium zirconium cyclosilicate were allopurinol, apixaban, aspirin, captopril, cyclosporine, digoxin, ethyl estradiol, lisinopril, magnesium, metformin, phenytoin, prednisone, propranolol, quinapril, spironolactone, and ticagrelor. Of the 23 drugs that showed an in vitro interaction, nine were subsequently tested in healthy volunteers. Losartan, glipizide, and levothyroxine did not demonstrate an in vivo interaction with sodium zirconium cyclosilicate. However, an increase in systemic exposure was observed for weak acids such as furosemide and atorvastatin when coadministered with sodium zirconium cyclosilicate, while a decrease in systemic exposure was observed for weak bases such as dabigatran.

MANAGEMENT: In general, concomitant oral medications should be administered at least 2 hours before or 2 hours after sodium zirconium cyclosilicate. Separation of dosing times is not needed if it has been determined that the concomitant medication does not exhibit pH-dependent solubility.

MONITOR: Many psychotherapeutic and CNS-active agents (e.g., anxiolytics, sedatives, hypnotics, antidepressants, antipsychotics, opioids, alcohol, muscle relaxants) exhibit hypotensive effects, especially during initiation of therapy and dose escalation. Coadministration with antihypertensives and other hypotensive agents, in particular vasodilators and alpha-blockers, may result in additive effects on blood pressure and orthostasis.

MANAGEMENT: Caution and close monitoring for development of hypotension is advised during coadministration of these agents. Some authorities recommend avoiding alcohol in patients receiving vasodilating antihypertensive drugs. Patients should be advised to avoid rising abruptly from a sitting or recumbent position and to notify their physician if they experience dizziness, lightheadedness, syncope, orthostasis, or tachycardia. Patients should also avoid driving or operating hazardous machinery until they know how the medications affect them.