(trye METH oh prim & pol i MIKS in bee)
Treatment of surface ocular bacterial conjunctivitis and blepharoconjunctivitis
Hypersensitivity to trimethoprim, polymyxin B, or any component of the formulation
Conjunctivitis, blepharoconjunctivitis: Ophthalmic: Instill 1 drop in affected eye(s) every 3 hours (maximum: 6 doses per day) for 7-10 days; has also been used 4 times daily for 5-7 days (Williams, 2013; The Wills Eye Manual, 2004)
Refer to adult dosing.
Children ≥2 months: Refer to adult dosing.
No dosage adjustment provided in manufacturer 's labeling.
No dosage adjustment provided in manufacturer 's labeling.
Avoid contamination of the applicator tip.
Store at 15 ‚ °C to 25 ‚ °C (59 ‚ °F to 77 ‚ °F); protect from light.
Excipient information presented when available (limited, particularly for generics); consult specific product labeling.
Solution, ophthalmic: Trimethoprim 1 mg and polymyxin B sulfate 10,000 units per 1 mL (10 mL)
Polytrim ‚ ®: Trimethoprim 1 mg and polymyxin B sulfate 10,000 units per 1 mL (10 mL) [contains benzalkonium chloride]
ACE Inhibitors: Trimethoprim may enhance the hyperkalemic effect of ACE Inhibitors. Monitor therapy
Amantadine: Trimethoprim may enhance the adverse/toxic effect of Amantadine. Specifically, the risk of myoclonus and/or delirium may be increased. Amantadine may increase the serum concentration of Trimethoprim. Trimethoprim may increase the serum concentration of Amantadine. Monitor therapy
Amodiaquine: Trimethoprim may enhance the neutropenic effect of Amodiaquine. Trimethoprim may increase the serum concentration of Amodiaquine. Avoid combination
Angiotensin II Receptor Blockers: Trimethoprim may enhance the hyperkalemic effect of Angiotensin II Receptor Blockers. Monitor therapy
Antidiabetic Agents (Thiazolidinedione): Trimethoprim may decrease the metabolism of Antidiabetic Agents (Thiazolidinedione). Monitor therapy
AzaTHIOprine: Trimethoprim may enhance the myelosuppressive effect of AzaTHIOprine. Monitor therapy
Bacitracin (Systemic): Polymyxin B may enhance the nephrotoxic effect of Bacitracin (Systemic). Avoid combination
BCG (Intravesical): Antibiotics may diminish the therapeutic effect of BCG (Intravesical). Avoid combination
BCG Vaccine (Immunization): Antibiotics may diminish the therapeutic effect of BCG Vaccine (Immunization). Monitor therapy
Bosentan: May decrease the serum concentration of CYP3A4 Substrates. Monitor therapy
Bosentan: CYP2C9 Inhibitors (Moderate) may increase the serum concentration of Bosentan. Management: Concomitant use of both a CYP2C9 inhibitor and a CYP3A inhibitor or a single agent that inhibits both enzymes with bosentan is likely to cause a large increase in serum concentrations of bosentan and is not recommended. See monograph for details. Monitor therapy
Cannabis: CYP2C9 Inhibitors (Moderate) may increase the serum concentration of Cannabis. More specifically, tetrahydrocannabinol serum concentrations may be increased. Monitor therapy
Capreomycin: May enhance the neuromuscular-blocking effect of Polymyxin B. Monitor therapy
Carvedilol: CYP2C9 Inhibitors (Moderate) may increase the serum concentration of Carvedilol. Specifically, concentrations of the S-carvedilol enantiomer may be increased. Monitor therapy
Cefazedone: May enhance the nephrotoxic effect of Polymyxin B. Monitor therapy
Ceritinib: May increase the serum concentration of CYP2C9 Substrates. Management: Concurrent use of ceritinib with a CYP2C9 substrate that has a narrow therapeutic index (e.g., warfarin, phenytoin) should be avoided when possible. Monitor therapy
Cholera Vaccine: Antibiotics may diminish the therapeutic effect of Cholera Vaccine. Avoid combination
Colistimethate: Polymyxin B may enhance the neuromuscular-blocking effect of Colistimethate. Monitor therapy
CYP2C8 Substrates: CYP2C8 Inhibitors (Moderate) may decrease the metabolism of CYP2C8 Substrates. Monitor therapy
CYP2C9 Inducers (Strong): May increase the metabolism of CYP2C9 Substrates. Management: Consider an alternative for one of the interacting drugs. Some combinations may be specifically contraindicated. Consult appropriate manufacturer labeling. Consider therapy modification
CYP2C9 Inhibitors (Moderate): May decrease the metabolism of CYP2C9 Substrates. Monitor therapy
CYP2C9 Inhibitors (Strong): May decrease the metabolism of CYP2C9 Substrates. Consider therapy modification
CYP2C9 Substrates: CYP2C9 Inhibitors (Moderate) may decrease the metabolism of CYP2C9 Substrates. Monitor therapy
CYP3A4 Inducers (Moderate): May decrease the serum concentration of CYP3A4 Substrates. Monitor therapy
CYP3A4 Inducers (Strong): May increase the metabolism of CYP3A4 Substrates. Management: Consider an alternative for one of the interacting drugs. Some combinations may be specifically contraindicated. Consult appropriate manufacturer labeling. Consider therapy modification
Dabrafenib: May decrease the serum concentration of CYP3A4 Substrates. Management: Seek alternatives to the CYP3A4 substrate when possible. If concomitant therapy cannot be avoided, monitor clinical effects of the substrate closely (particularly therapeutic effects). Consider therapy modification
Dabrafenib: May decrease the serum concentration of CYP2C9 Substrates. Management: Seek alternatives to the CYP2C9 substrate when possible. If concomitant therapy cannot be avoided, monitor clinical effects of the substrate closely (particularly therapeutic effects). Consider therapy modification
Dapsone (Systemic): Trimethoprim may increase the serum concentration of Dapsone (Systemic). Dapsone (Systemic) may increase the serum concentration of Trimethoprim. Monitor therapy
Dapsone (Topical): Trimethoprim may enhance the adverse/toxic effect of Dapsone (Topical). More specifically, trimethoprim may increase the risk for hemolysis Monitor therapy
Deferasirox: May decrease the serum concentration of CYP3A4 Substrates. Monitor therapy
Digoxin: Trimethoprim may increase the serum concentration of Digoxin. Monitor therapy
Dofetilide: Trimethoprim may decrease the excretion of Dofetilide. Avoid combination
Dronabinol: CYP2C9 Inhibitors (Moderate) may increase the serum concentration of Dronabinol. Monitor therapy
Enzalutamide: May decrease the serum concentration of CYP3A4 Substrates. Management: Concurrent use of enzalutamide with CYP3A4 substrates that have a narrow therapeutic index should be avoided. Use of enzalutamide and any other CYP3A4 substrate should be performed with caution and close monitoring. Consider therapy modification
Enzalutamide: May decrease the serum concentration of CYP2C9 Substrates. Management: Concurrent use of enzalutamide with CYP2C9 substrates that have a narrow therapeutic index should be avoided. Use of enzalutamide and any other CYP2C9 substrate should be performed with caution and close monitoring. Consider therapy modification
Eplerenone: Trimethoprim may enhance the hyperkalemic effect of Eplerenone. Monitor therapy
Fosphenytoin: May decrease the serum concentration of Trimethoprim. Trimethoprim may increase the serum concentration of Fosphenytoin. Management: Consider alternatives to this combination when possible, to avoid potential decreased trimethoprim efficacy and increased phenytoin concentrations/effects. Monitor patients receiving this combination closely for both of these possible effects. Consider therapy modification
Highest Risk QTc-Prolonging Agents: QTc-Prolonging Agents (Indeterminate Risk and Risk Modifying) may enhance the QTc-prolonging effect of Highest Risk QTc-Prolonging Agents. Management: Avoid such combinations when possible. Use should be accompanied by close monitoring for evidence of QT prolongation or other alterations of cardiac rhythm. Consider therapy modification
Lactobacillus and Estriol: Antibiotics may diminish the therapeutic effect of Lactobacillus and Estriol. Monitor therapy
LamiVUDine: Trimethoprim may decrease the excretion of LamiVUDine. Monitor therapy
Leucovorin Calcium-Levoleucovorin: May diminish the therapeutic effect of Trimethoprim. Management: Avoid concurrent use of leucovorin or levoleucovorin with trimethoprim (plus sulfamethoxazole) for Pneumocystis jiroveci pneumonia. If trimethoprim is used for another indication, monitor closely for reduced efficacy. Avoid combination
Mecamylamine: Polymyxin B may enhance the neuromuscular-blocking effect of Mecamylamine. Avoid combination
Memantine: Trimethoprim may enhance the adverse/toxic effect of Memantine. Specifically, the risk of myoclonus and/or delirium may be increased. Trimethoprim may increase the serum concentration of Memantine. Memantine may increase the serum concentration of Trimethoprim. Monitor therapy
Mercaptopurine: Trimethoprim may enhance the myelosuppressive effect of Mercaptopurine. Monitor therapy
MetFORMIN: Trimethoprim may increase the serum concentration of MetFORMIN. Monitor therapy
Methotrexate: Trimethoprim may enhance the adverse/toxic effect of Methotrexate. Management: Consider avoiding concomitant use of methotrexate and either sulfamethoxazole or trimethoprim. If used concomitantly, monitor for the development of signs and symptoms of methotrexate toxicity (e.g., bone marrow suppression). Consider therapy modification
MiFEPRIStone: May increase the serum concentration of CYP2C9 Substrates. Management: Use CYP2C9 substrates at the lowest recommended dose, and monitor closely for adverse effects, during and in the 2 weeks following mifepristone treatment. Consider therapy modification
MiFEPRIStone: May enhance the QTc-prolonging effect of QTc-Prolonging Agents (Indeterminate Risk and Risk Modifying). Management: Though the drugs listed here have uncertain QT-prolonging effects, they all have some possible association with QT prolongation and should generally be avoided when possible. Consider therapy modification
Mitotane: May decrease the serum concentration of CYP3A4 Substrates. Management: Doses of CYP3A4 substrates may need to be adjusted substantially when used in patients being treated with mitotane. Consider therapy modification
Moderate Risk QTc-Prolonging Agents: QTc-Prolonging Agents (Indeterminate Risk and Risk Modifying) may enhance the QTc-prolonging effect of Moderate Risk QTc-Prolonging Agents. Monitor therapy
Neuromuscular-Blocking Agents: Polymyxin B may enhance the neuromuscular-blocking effect of Neuromuscular-Blocking Agents. Consider therapy modification
Osimertinib: May increase the serum concentration of CYP3A4 Substrates. Osimertinib may decrease the serum concentration of CYP3A4 Substrates. Monitor therapy
Phenytoin: Trimethoprim may increase the serum concentration of Phenytoin. Phenytoin may decrease the serum concentration of Trimethoprim. Management: Consider alternatives to this combination when possible, to avoid potential decreased trimethoprim efficacy and increased phenytoin concentrations/effects. Monitor patients receiving this combination closely for both of these possible effects. Consider therapy modification
PRALAtrexate: Trimethoprim may increase the serum concentration of PRALAtrexate. More specifically, trimethoprim may decrease excretion of pralatrexate. Management: Closely monitor for increased pralatrexate serum level and/or possible toxicity with concomitant use of trimethoprim. Monitor for decreased pralatrexate levels with discontinuation of trimethoprim. Monitor therapy
Procainamide: Trimethoprim may increase serum concentrations of the active metabolite(s) of Procainamide. Trimethoprim may increase the serum concentration of Procainamide. Consider therapy modification
Repaglinide: Trimethoprim may decrease the metabolism of Repaglinide. Monitor therapy
Siltuximab: May decrease the serum concentration of CYP3A4 Substrates. Monitor therapy
Sodium Picosulfate: Antibiotics may diminish the therapeutic effect of Sodium Picosulfate. Management: Consider using an alternative product for bowel cleansing prior to a colonoscopy in patients who have recently used or are concurrently using an antibiotic. Consider therapy modification
Spironolactone: Trimethoprim may enhance the hyperkalemic effect of Spironolactone. Monitor therapy
St Johns Wort: May decrease the serum concentration of CYP3A4 Substrates. Management: Consider an alternative for one of the interacting drugs. Some combinations may be specifically contraindicated. Consult appropriate manufacturer labeling. Consider therapy modification
Tetrahydrocannabinol: CYP2C9 Inhibitors (Moderate) may increase the serum concentration of Tetrahydrocannabinol. Monitor therapy
Tocilizumab: May decrease the serum concentration of CYP3A4 Substrates. Monitor therapy
Typhoid Vaccine: Antibiotics may diminish the therapeutic effect of Typhoid Vaccine. Only the live attenuated Ty21a strain is affected. Management: Vaccination with live attenuated typhoid vaccine (Ty21a) should be avoided in patients being treated with systemic antibacterial agents. Use of this vaccine should be postponed until at least 3 days after cessation of antibacterial agents. Consider therapy modification
Varenicline: Trimethoprim may increase the serum concentration of Varenicline. Management: Monitor for increased varenicline adverse effects with concomitant use of trimethoprim, particularly in patients with severe renal impairment. International product labeling recommendations vary. Consult appropriate labeling. Monitor therapy
Frequency not defined: Ocular: Burning, itching, edema, rash, redness increased, stinging, tearing
See individual agents.
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Adverse events have been observed with trimethoprim in animal reproduction studies; animal reproduction studies have not been conducted with polymyxin B. See individual agents. If ophthalmic agents are needed during pregnancy, the minimum effective dose should be used in combination with punctual occlusion to decrease potential exposure to the fetus (Samples, 1988).
Trimethoprim and polymyxin B are systemically absorbed following ophthalmic installation. Peak concentrations were trimethoprim 0.03 mcg/mL and polymyxin B 1 unit/mL.
- Discuss specific use of drug and side effects with patient as it relates to treatment. (HCAHPS: During this hospital stay, were you given any medicine that you had not taken before? Before giving you any new medicine, how often did hospital staff tell you what the medicine was for? How often did hospital staff describe possible side effects in a way you could understand?)
- Patient may experience burning, stinging, or itching. Have patient report immediately to prescriber vision changes, eye pain, severe eye irritation, or eyelid edema (HCAHPS).
- Educate patient about signs of a significant reaction (eg, wheezing; chest tightness; fever; itching; bad cough; blue skin color; seizures; or swelling of face, lips, tongue, or throat). Note: This is not a comprehensive list of all side effects. Patient should consult prescriber for additional questions.
Intended Use and Disclaimer: Should not be printed and given to patients. This information is intended to serve as a concise initial reference for health care professionals to use when discussing medications with a patient. You must ultimately rely on your own discretion, experience, and judgment in diagnosing, treating, and advising patients.