Polymyxin-B/trimethoprim Ophth Sol
It is used to treat eye infections.
Drug Class
Ophthalmic Anti-infective
Pharmacologic Class
Antibiotic (Polymyxin B: Polypeptide; Trimethoprim: Dihydrofolate Reductase Inhibitor)
Pregnancy Category
Category C
FDA Approved
Jun 1981
DEA Schedule
Not Controlled
Overview
What is this medicine?
This medication is an antibiotic eye drop used to treat bacterial infections of the eye, such as pink eye (bacterial conjunctivitis). It contains two different antibiotics, trimethoprim and polymyxin B, which work together to kill the bacteria causing the infection.
How to Use This Medicine
Taking Your Medication Correctly
To use this medication safely and effectively, follow your doctor's instructions and the information provided with your prescription. Continue using the medication as directed, even if your symptoms improve.
Administering the Medication
This medication is for use in the eye only. To avoid contamination and potential severe eye problems or vision loss, do not touch the container tip to your eye, eyelid, or surrounding skin.
1. Tilt your head back and gently drop the medication into your eye.
2. After administering the medication, keep your eye closed and apply gentle pressure to the inside corner of your eye for 1 to 2 minutes. This helps retain the medication in your eye.
Storing and Disposing of Your Medication
To maintain the medication's effectiveness and safety:
- Store the medication at room temperature, protected from light and moisture. Avoid storing it in a bathroom.
- Keep all medications in a secure location, out of the reach of children and pets.
- Dispose of unused or expired medications properly. Do not flush them down the toilet or pour them down the drain unless instructed to do so by your pharmacist. Check with your pharmacist for guidance on the best disposal method or to see if there are drug take-back programs available in your area.
Missing a Dose
If you miss a dose, take it as soon as you remember. However, if it is close to the time for your next scheduled dose, skip the missed dose and resume your regular dosing schedule. Do not take two doses at once or extra doses to make up for a missed dose.
To use this medication safely and effectively, follow your doctor's instructions and the information provided with your prescription. Continue using the medication as directed, even if your symptoms improve.
Administering the Medication
This medication is for use in the eye only. To avoid contamination and potential severe eye problems or vision loss, do not touch the container tip to your eye, eyelid, or surrounding skin.
1. Tilt your head back and gently drop the medication into your eye.
2. After administering the medication, keep your eye closed and apply gentle pressure to the inside corner of your eye for 1 to 2 minutes. This helps retain the medication in your eye.
Storing and Disposing of Your Medication
To maintain the medication's effectiveness and safety:
- Store the medication at room temperature, protected from light and moisture. Avoid storing it in a bathroom.
- Keep all medications in a secure location, out of the reach of children and pets.
- Dispose of unused or expired medications properly. Do not flush them down the toilet or pour them down the drain unless instructed to do so by your pharmacist. Check with your pharmacist for guidance on the best disposal method or to see if there are drug take-back programs available in your area.
Missing a Dose
If you miss a dose, take it as soon as you remember. However, if it is close to the time for your next scheduled dose, skip the missed dose and resume your regular dosing schedule. Do not take two doses at once or extra doses to make up for a missed dose.
Lifestyle & Tips
- Wash hands thoroughly before and after applying eye drops.
- Do not touch the dropper tip to your eye or any other surface to prevent contamination.
- Remove contact lenses before applying drops and wait at least 15 minutes before reinserting them (or avoid wearing them until the infection clears).
- Do not share eye drops with others.
- Complete the full course of treatment, even if symptoms improve, to prevent recurrence and antibiotic resistance.
- Avoid rubbing your eyes.
Available Forms & Alternatives
Available Strengths:
Dosing & Administration
Adult Dosing
Standard Dose:
1 drop in the affected eye(s) every 3 hours for 7-10 days
Condition-Specific Dosing:
bacterial conjunctivitis:
1 drop in the affected eye(s) every 3 hours for 7-10 days, or as directed by physician. Dosing frequency may be reduced as infection improves.
Pediatric Dosing
Neonatal:
Not established (use with caution, consult ophthalmologist)
Infant:
1 drop in the affected eye(s) every 3 hours for 7-10 days (typically for children âĨ2 months of age, consult physician)
Child:
1 drop in the affected eye(s) every 3 hours for 7-10 days
Adolescent:
1 drop in the affected eye(s) every 3 hours for 7-10 days
Dose Adjustments
Renal Impairment:
Mild:
No adjustment needed (minimal systemic absorption)
Moderate:
No adjustment needed (minimal systemic absorption)
Severe:
No adjustment needed (minimal systemic absorption)
Dialysis:
No specific considerations for ophthalmic use due to minimal systemic absorption
Hepatic Impairment:
Mild:
No adjustment needed (minimal systemic absorption)
Moderate:
No adjustment needed (minimal systemic absorption)
Severe:
No adjustment needed (minimal systemic absorption)
Pharmacology
Mechanism of Action
Polymyxin B is a bactericidal antibiotic that acts by increasing the permeability of the bacterial cell membrane, causing leakage of intracellular contents. It is effective against Gram-negative bacteria. Trimethoprim is a bacteriostatic antibiotic that inhibits bacterial dihydrofolate reductase, thereby blocking the synthesis of tetrahydrofolic acid, an essential precursor in the biosynthesis of DNA and RNA. This dual mechanism provides broad-spectrum antibacterial activity.
Pharmacokinetics
Absorption:
Bioavailability:
Negligible systemic absorption from ophthalmic administration
Tmax:
Not applicable (minimal systemic absorption)
FoodEffect:
Not applicable (ophthalmic administration)
Distribution:
Vd:
Not applicable (minimal systemic absorption)
ProteinBinding:
Not applicable (minimal systemic absorption)
CnssPenetration:
No (minimal systemic absorption)
Elimination:
HalfLife:
Not applicable (minimal systemic absorption)
Clearance:
Not applicable (minimal systemic absorption)
ExcretionRoute:
Not applicable (minimal systemic absorption)
Unchanged:
Not applicable (minimal systemic absorption)
Pharmacodynamics
OnsetOfAction:
Within hours to days (clinical improvement typically seen within 2-3 days)
PeakEffect:
Within 2-3 days of consistent use
DurationOfAction:
Dependent on dosing frequency (e.g., 3 hours for q3h dosing)
Safety & Warnings
Side Effects
Urgent Side Effects: Seek Medical Help Right Away
While rare, some people may experience severe and potentially life-threatening side effects when taking this medication. If you notice any of the following symptoms, contact your doctor or seek immediate medical attention:
Signs of an allergic reaction, such as:
+ Rash
+ Hives
+ Itching
+ Red, swollen, blistered, or peeling skin with or without fever
+ Wheezing
+ Tightness in the chest or throat
+ Trouble breathing, swallowing, or talking
+ Unusual hoarseness
+ Swelling of the mouth, face, lips, tongue, or throat
Changes in eyesight, eye pain, or severe eye irritation
Eyelid swelling
Other Possible Side Effects
Like all medications, this drug can cause side effects. Although many people may not experience any side effects or only minor ones, it's essential to discuss any concerns with your doctor. If you experience any of the following side effects or any other unusual symptoms that bother you or persist, contact your doctor for advice:
Eye irritation
Burning or stinging
Itching
This list is not exhaustive, and you may experience other side effects not mentioned here. If you have questions or concerns about side effects, don't hesitate to reach out to your doctor. You can also report side effects to the FDA at 1-800-332-1088 or online at https://www.fda.gov/medwatch.
While rare, some people may experience severe and potentially life-threatening side effects when taking this medication. If you notice any of the following symptoms, contact your doctor or seek immediate medical attention:
Signs of an allergic reaction, such as:
+ Rash
+ Hives
+ Itching
+ Red, swollen, blistered, or peeling skin with or without fever
+ Wheezing
+ Tightness in the chest or throat
+ Trouble breathing, swallowing, or talking
+ Unusual hoarseness
+ Swelling of the mouth, face, lips, tongue, or throat
Changes in eyesight, eye pain, or severe eye irritation
Eyelid swelling
Other Possible Side Effects
Like all medications, this drug can cause side effects. Although many people may not experience any side effects or only minor ones, it's essential to discuss any concerns with your doctor. If you experience any of the following side effects or any other unusual symptoms that bother you or persist, contact your doctor for advice:
Eye irritation
Burning or stinging
Itching
This list is not exhaustive, and you may experience other side effects not mentioned here. If you have questions or concerns about side effects, don't hesitate to reach out to your doctor. You can also report side effects to the FDA at 1-800-332-1088 or online at https://www.fda.gov/medwatch.
Seek Immediate Medical Attention If You Experience:
- Worsening eye redness, pain, or discharge
- New or worsening blurred vision
- Severe eye irritation or burning after applying drops
- Signs of an allergic reaction (e.g., rash, itching, swelling of the face/tongue/throat, severe dizziness, trouble breathing)
- Development of new eye symptoms
Before Using This Medicine
Before Taking This Medication: Important Information to Share with Your Doctor
It is essential to inform your doctor about any allergies you have, including:
Allergies to this medication or any of its components
Allergies to other medications, foods, or substances
The specific symptoms you experienced as a result of the allergy
Additionally, this medication may interact with other medications or health conditions. To ensure safe use, please disclose the following information to your doctor and pharmacist:
All prescription and over-the-counter medications you are currently taking
Any natural products or vitamins you are using
Any existing health problems or conditions
It is crucial to verify that it is safe to take this medication in combination with your other medications and health conditions. Do not initiate, discontinue, or modify the dosage of any medication without first consulting your doctor.
It is essential to inform your doctor about any allergies you have, including:
Allergies to this medication or any of its components
Allergies to other medications, foods, or substances
The specific symptoms you experienced as a result of the allergy
Additionally, this medication may interact with other medications or health conditions. To ensure safe use, please disclose the following information to your doctor and pharmacist:
All prescription and over-the-counter medications you are currently taking
Any natural products or vitamins you are using
Any existing health problems or conditions
It is crucial to verify that it is safe to take this medication in combination with your other medications and health conditions. Do not initiate, discontinue, or modify the dosage of any medication without first consulting your doctor.
Precautions & Cautions
It is essential to inform all your healthcare providers, including doctors, nurses, pharmacists, and dentists, that you are taking this medication. When taking this drug, exercise caution while driving or performing tasks that require clear vision to ensure your safety. Do not exceed the prescribed duration of use, as this may increase the risk of a secondary infection. If you are pregnant, planning to become pregnant, or are breastfeeding, consult your doctor to discuss the potential benefits and risks of this medication to both you and your baby.
Overdose Information
Overdose Symptoms:
- Unlikely with ophthalmic use due to minimal systemic absorption. Accidental oral ingestion of a small amount is generally not expected to cause serious toxicity.
What to Do:
If accidental ingestion occurs, drink fluids. If a large amount is ingested or if symptoms develop, contact a poison control center (1-800-222-1222) or seek medical attention.
Drug Interactions
Monitoring
Baseline Monitoring
Visual acuity
Rationale: To establish baseline and monitor for improvement or worsening of vision due to infection.
Timing: Prior to initiation of therapy
Signs and symptoms of bacterial conjunctivitis (e.g., redness, discharge, irritation, pain, swelling)
Rationale: To confirm diagnosis and establish baseline severity.
Timing: Prior to initiation of therapy
Routine Monitoring
Resolution of signs and symptoms of infection
Frequency: Daily
Target: Improvement leading to resolution
Action Threshold: If symptoms worsen or do not improve within 2-3 days, re-evaluate diagnosis and treatment.
Adverse ocular reactions (e.g., burning, stinging, itching, redness, swelling)
Frequency: Daily
Target: Absence or mild, transient reactions
Action Threshold: Discontinue if severe or persistent irritation, or signs of allergic reaction occur.
Symptom Monitoring
- Increased eye redness
- Increased eye discharge
- Increased eye pain or discomfort
- Blurred vision
- Swelling around the eye
- Itching or burning sensation in the eye
- Signs of allergic reaction (e.g., rash, hives, severe itching, difficulty breathing, swelling of face/lips/tongue/throat)
Special Patient Groups
Pregnancy
Use during pregnancy should be considered only if the potential benefit justifies the potential risk to the fetus. While classified as Category C, systemic absorption from ophthalmic use is minimal, suggesting a low risk.
Trimester-Specific Risks:
First Trimester:
Low risk due to minimal systemic absorption, but caution advised.
Second Trimester:
Low risk due to minimal systemic absorption.
Third Trimester:
Low risk due to minimal systemic absorption.
Lactation
Considered low risk for nursing infants due to minimal systemic absorption of the active ingredients from ophthalmic administration. Monitor infant for potential diarrhea or rash.
Infant Risk:
Low risk
Pediatric Use
Generally safe and effective for use in pediatric patients, including infants (typically âĨ2 months of age) for bacterial conjunctivitis. Dosing is similar to adults. Safety and efficacy in neonates (under 2 months) have not been fully established, and use should be under strict medical supervision.
Geriatric Use
No specific dosage adjustments are necessary for geriatric patients. The safety and efficacy profile is similar to that in younger adults.
Clinical Information
Clinical Pearls
- This combination ophthalmic solution is particularly useful for bacterial conjunctivitis caused by susceptible organisms, especially when Gram-negative coverage is desired.
- Patients should be instructed on proper eye drop instillation technique to maximize efficacy and minimize contamination.
- Advise patients to avoid wearing contact lenses during treatment of bacterial conjunctivitis.
- If symptoms do not improve within 2-3 days, or worsen, re-evaluate the diagnosis and consider alternative treatments or cultures.
- Transient stinging or burning upon instillation is common and usually resolves quickly.
Alternative Therapies
- Moxifloxacin ophthalmic solution
- Gatifloxacin ophthalmic solution
- Azithromycin ophthalmic solution
- Tobramycin ophthalmic solution
- Erythromycin ophthalmic ointment
- Sulfacetamide ophthalmic solution/ointment
Cost & Coverage
Average Cost:
$20 - $50 per 10 mL bottle
Generic Available:
Yes
Insurance Coverage:
Tier 1 or 2 (preferred generic)
General Drug Facts
If your symptoms or health issues persist or worsen, it's essential to contact your doctor for further guidance. To ensure your safety, never share your medication with others or take someone else's medication. Some medications may come with an additional patient information leaflet, so be sure to check with your pharmacist for more information. If you have any questions or concerns about your medication, don't hesitate to reach out to your doctor, nurse, pharmacist, or other healthcare provider. In the event of a suspected overdose, immediately call your local poison control center or seek medical attention. When seeking help, be prepared to provide details about the medication taken, the amount, and the time it occurred.