Tobramycin (Tobrex) is an antibiotic that's used to treat different types of bacterial eye infections. It can be used for people ages 2 months and older. Tobramycin (Tobrex) comes as an ophthalmic solution (eye drops) and eye ointment that are used multiple times per day. It's available in both brand-name and generic versions. The most common side effects include eyelid itching, eyelid swelling, and eye redness. Like with all antibiotics, you shouldn't stop treatment too early because your infection could come back or get harder to treat.
Bacterial infections of the eye or eyelid
Tobramycin (Tobrex) is an aminoglycoside antibiotic. It kills bacteria by blocking their ability to make proteins and by damaging their protective covering.
Source:Â DailyMed
Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.
Check with your doctor immediately if any of the following side effects occur:
Less common
Itching, redness, swelling, or other sign of eye or eyelid irritation not present before use of this medicine
Symptoms of overdose
Increased watering of the eyes
itching, redness, or swelling of the eyes or eyelids
painful irritation of the clear front part of the eye
Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:
Less common
Burning or stinging of the eyes
Eye ointments usually cause your vision to blur for a few minutes after application.
Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.
Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.
Treats various bacterial eye and eyelid infections
Ointment form requires fewer doses per day than most alternatives
Eye drop form is available as a lower-cost generic
Can cause temporary eye irritation
Might require more frequent dosing throughout the day for severe infections
Ointment form tends to be messy and harder to put in the eye
Be sure to use tobramycin (Tobrex) for the full amount of time that your healthcare provider instructs, even if your eye starts to get better. Stopping tobramycin (Tobrex) too soon can cause your infection to come back and be harder to treat.
Wash your hands before and after using tobramycin (Tobrex). Don't let the tip of the container touch your eye, hands, or any other surface. This will help you avoid spreading germs to the medication and to your eyes.
Don't put any other medications in the eye for at least 5 minutes before or after tobramycin (Tobrex).
It's best not to wear contacts while you have an eye infection, since this can affect how quickly your symptoms improve. Be sure to throw away the contacts you were wearing before you started using tobramycin (Tobrex). They probably have bacteria on them. Wear a new pair of contacts once your infection is cleared up.
How to use tobramycin (Tobrex) eye drops: To use the eye drops, tilt your head back a little and look up. Pull your lower eyelid down with one hand. With the other hand, hold the eye drop bottle upside down and close to your eye. Then, squeeze the number of drops you need into your eye. After placing the drop(s) in your eye, close your eye and press one finger to the inner corner of your eye by the nose for 1 to 2 minutes. This helps make sure your eye absorbs the medication.
How to use tobramycin (Tobrex) eye ointment: Tilt your head back a little and gently pull down your lower eyelid. Put the ointment into the space between your eyelid and eyeball. Then, let go of the eyelid and close your eye for 1 to 2 minutes, so the medication is able to reach all the necessary parts of the eye. Roll your eyeball around in the meantime. If you want to wipe off extra ointment or greasiness on the outside the eye, do it carefully and make sure you're using a clean tissue. Eye ointments usually cause blurry vision, but this should only last a couple minutes.
Tobramycin (Tobrex) can cause some serious health issues. This risk may be even higher for certain groups. If this worries you, talk to your doctor or pharmacist about other options.
Risk factors: Using tobramycin (Tobrex) for too long
It's possible to get a new infection from fungi or bacteria after using tobramycin (Tobrex) for a while. Sometimes, these new infections can be hard to treat and can no longer be treated with tobramycin (Tobrex). Don't use this medication longer than prescribed. Let your provider know if you notice symptoms of a new infection or if the original symptoms don't get better after using tobramycin (Tobrex).
Risk factors: Allergy to other aminoglycoside antibiotics
Tobramycin (Tobrex) can sometimes cause an allergic reaction, such as redness, itching, or rash. If you experience any of these symptoms, stop using the medication and contact your provider.
In some rare cases, the allergy can be serious and cause anaphylaxis (which can cause your throat to close). Call 911 or get medical attention right away if you're having a severe allergic reaction.
Let your provider know if you've had allergic reactions in the past to other aminoglycoside antibiotics like gentamicin (Gentak) eye drops.
Don't wear contact lenses while using tobramycin (Tobrex), since it can affect how quickly your symptoms improve. Throw away the lenses you were wearing before you started using tobramycin (Tobrex) because they'll most likely have bacteria on them. If you're still having symptoms of your infection after you've finished your tobramycin (Tobrex) treatment course, don't start wearing contacts again yet because you might still have an infection.
Eye ointments like tobramycin (Tobrex) might slow healing of the cornea (the protective covering in the front of the eye). Remember to follow up with your provider to make sure that your eye is healing appropriately.
If you use contaminated tobramycin (Tobrex) eye drops or eye ointments, you can develop a new eye infection or make your eye infection worse. Wash your hands each time before you use the eye drops or eye ointment. Don't touch the tip of the container to your eye, with your hands, or to any other surface. Remember to put the cap back on the container after each use.
Eye drops: For mild-to-moderate infections, place 1 or 2 drops in the affected eye(s) every 4 hours. For severe infections, you'll typically start off using 2 drops every hour until the symptoms have improved.
Eye ointment: For mild-to-moderate infections, apply a half-inch-sized ribbon to the affected eye(s) 2 or 3 times per day. For severe infections, you'll typically start off using it every 3 to 4 hours until symptoms have improved.
Using this medicine with any of the following medicines is not recommended. Your doctor may decide not to treat you with this medication or change some of the other medicines you take.
Using this medicine with any of the following medicines is usually not recommended, but may be required in some cases. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
Using this medicine with any of the following medicines may cause an increased risk of certain side effects, but using both drugs may be the best treatment for you. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
Bacterial infections of the eye or eyelid
Bacterial infections of the eye or eyelid
By signing up, I agree to GoodRx's Terms and Privacy Policy, and to receive marketing messages from GoodRx.
Alcon Laboratories, Inc. (2023). Tobrex [package insert]. DailyMed.
Alembic Pharmaceuticals Inc. (2022). Tobramycin ophthalmic solution - tobramycin ophthalmic solution solution/ drops [package insert]. DailyMed.
Krause, K. M., et al. (2016). Aminoglycosides: An overview. Cold Spring Harbor Perspectives in Medicine.
National Eye Institute. (2021). How to put in eye drops.
Porter, D. (2022). Antibiotic eye drops. American Academy of Ophthalmology.
SafeMedication. (n.d.). How to use eye ointments and gels.
Research prescriptions and over-the-counter medications from A to Z, compare drug prices, and start saving.