Pronunciation:

toe-bra-MYE-sin

Brand Names:

• AKTob
• Tobrasol
• Tobrex
• Apo-Tobramycin
• Sab-Tobramycin
• Tomycine

Dosage Forms:

• Solution
• Ointment

Warnings:

Patients treated with tobramycin for injection USP and other aminoglycosides should be under close clinical observation, because these drugs have an inherent potential for causing ototoxicity and nephrotoxicity. Neurotoxicity, manifested as both auditory and vestibular ototoxicity, can occur. The auditory changes are irreversible, are usually bilateral, and may be partial or total. Eighth-nerve impairment and nephrotoxicity may develop, primarily in patients having preexisting renal damage and in those with normal renal function to whom aminoglycosides are administered for longer periods or in higher doses than those recommended. Other manifestations of neurotoxicity may include numbness, skin tingling, muscle twitching, and convulsions. The risk of aminoglycoside-induced hearing loss increases with the degree of exposure to either high peak or high trough serum concentrations. Patients who develop cochlear damage may not have symptoms during therapy to warn them of eighth-nerve toxicity, and partial or total irreversible bilateral deafness may continue to develop after the drug has been discontinued.

Rarely, nephrotoxicity may become apparent until the first few days after cessation of therapy. Aminoglycoside-induced nephrotoxicity usually is reversible.

Renal and eighth-nerve function should be closely monitored in patients with known or suspected renal impairment and also in those whose renal function is initially normal but who develop signs of renal dysfunction during therapy. Peak and trough serum concentrations of aminoglycosides should be monitored periodically during therapy to assure adequate levels and to avoid potentially toxic levels. Prolonged serum concentrations above 12 mcg/mL should be avoided. Rising trough levels (above 2 mcg/mL) may indicate tissue accumulation. Such accumulation, excessive peak concentrations, advanced age, and cumulative dose may contribute to ototoxicity and nephrotoxicity. Urine should be examined for decreased specific gravity and increased excretion of protein, cells, and casts. Blood urea nitrogen, serum creatinine, and creatinine clearance should be measured periodically. When feasible, it is recommended that serial audiograms be obtained in patients old enough to be tested, particularly high-risk patients. Evidence of impairment of renal, vestibular, or auditory function requires discontinuation of the drug or dosage adjustment.

Tobramycin for injection USP should be used with caution in premature and neonatal infants because of their renal immaturity and the resulting prolongation of serum half-life of the drug.

Concurrent and sequential use of other neurotoxic and/or nephrotoxic antibiotics, particularly other aminoglycosides (eg amikacin, streptomycin, neomycin, kanamycin, gentamicin, and paromomycin), cephaloridine, viomycin, polymycin B, colistin, cisplatin, and vancomycin, should be avoided. Other factors that may increase patient risk are advanced age and dehydration.

Aminoglycosides should not be given concurrently with potent diuretics, such as ethacrynic acid and furosemide. Some diuretics themselves cause ototoxicity, and intravenously administered diuretics enhance aminoglycoside toxicity by altering antibiotic concentrations in serum and tissue.

Aminoglycosides can cause fetal harm when administered to a pregnant woman .

Therapy has been associated with potential neurotoxicity, ototoxicity, and nephrotoxicity. Patients with impaired renal function, advanced age, dehydration, and those who receive high dosage or prolonged therapy are at an increased risk of toxicity. Monitor renal and auditory function during therapy and discontinue therapy or adjust dose if there is evidence of ototoxicity or nephrotoxicity. Aminoglycoside-induced ototoxicity is usually irreversible. Serum concentrations of aminoglycosides should be monitored periodically to assure adequate levels and to avoid potentially toxic levels. Concurrent use of other potentially neurotoxic or nephrotoxic agents, or potent diuretics should be avoided. Tobramycin should be used with caution in premature and neonatal infants because of their renal immaturity and the resulting prolongation of serum half-life of the drug. Aminoglycosides can cause fetal harm when administered to a pregnant woman .

Classifications:

Therapeutic—

Antibiotic

Chemical—

Aminoglycoside

Uses of This Medicine:

Ophthalmic tobramycin is used in the eye to treat bacterial infections of the eye. Tobramycin works by killing bacteria.

Ophthalmic tobramycin may be used alone or with other medicines for eye infections. Either the drops or the ointment form of this medicine may be used alone during the day. In addition, both forms may be used together, with the drops being used during the day and the ointment at night.

Tobramycin ophthalmic preparations are available only with your doctor's prescription.

Before Using This Medicine:

In deciding to use a medicine, the risks of taking the medicine must be weighed against the good it will do. This is a decision you and your doctor will make. For this medicine, the following should be considered:

Allergies—

Tell your doctor if you have ever had any unusual or allergic reaction to this medicine or any other medicines. Also tell your health care professional if you have any other types of allergies, such as to foods, dyes, preservatives, or animals. For non-prescription products, read the label or package ingredients carefully.

Children—

This medicine has been tested in children and, in effective doses, has not been shown to cause different side effects or problems than it does in adults.

Older adults—

Many medicines have not been studied specifically in older people. Therefore, it may not be known whether they work exactly the same way they do in younger adults or if they cause different side effects or problems in older people. There is no specific information comparing use of ophthalmic tobramycin in the elderly with use in other age groups.

Pregnancy—

	Pregnancy Category	Explanation
All Trimesters	D	Studies in pregnant women have demonstrated a risk to the fetus. However, the benefits of therapy in a life threatening situation or a serious disease, may outweigh the potential risk.

Breast-feeding—

There are no adequate studies in women for determining infant risk when using this medication during breastfeeding. Weigh the potential benefits against the potential risks before taking this medication while breastfeeding.

Other medicines—

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.

• Alcuronium
• Atracurium
• Cidofovir
• Cisatracurium
• Decamethonium
• Doxacurium
• Fazadinium
• Gallamine
• Hexafluorenium
• Lysine
• Metocurine
• Mivacurium
• Pancuronium
• Pipecuronium
• Rapacuronium
• Rocuronium
• Succinylcholine
• Tacrolimus
• Tubocurarine
• Vecuronium

Other interactions—

Certain medicines should not be used at or around the time of eating food or eating certain types of food since interactions may occur. Using alcohol or tobacco with certain medicines may also cause interactions to occur. Discuss with your healthcare professional the use of your medicine with food, alcohol, or tobacco.

Proper Use of This Medicine:

For patients using tobramycin ophthalmic solution (eye drops):

• The bottle is only partially full to provide proper drop control.
• To use:
  • First, wash your hands. Tilt the head back and with the index finger of one hand, press gently on the skin just beneath the lower eyelid and pull the lower eyelid away from the eye to make a space. Drop the medicine into this space. Let go of the eyelid and gently close the eyes. Do not blink. Keep the eyes closed for 1 or 2 minutes, to allow the medicine to come into contact with the infection.
  • If you think you did not get the drop of medicine into your eye properly, use another drop.
  • To keep the medicine as germ-free as possible, do not touch the applicator tip to any surface (including the eye). Also, keep the container tightly closed.
• If your doctor ordered two different ophthalmic solutions to be used together, wait at least 5 minutes between the times you apply the medicines. This will help to keep the second medicine from ``washing out'' the first one.

For patients using tobramycin ophthalmic ointment (eye ointment):

• To use:
  • First, wash your hands. Tilt the head back and with the index finger of one hand, press gently on the skin just beneath the lower eyelid and pull the lower eyelid away from the eye to make a space. Squeeze a thin strip of ointment into this space. A 1.25-cm (approximately ½-inch) strip of ointment usually is enough, unless you have been told by your doctor to use a different amount. Let go of the eyelid and gently close the eyes and keep them closed for 1 or 2 minutes, to allow the medicine to come into contact with the infection.
  • To keep the medicine as germ-free as possible, do not touch the applicator tip to any surface (including the eye). After using tobramycin eye ointment, wipe the tip of the ointment tube with a clean tissue and keep the tube tightly closed.

To help clear up your eye infection completely, keep using tobramycin for the full time of treatment, even if your symptoms have disappeared. Do not miss any doses.

Dosing—

The dose of this medicine will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of this medicine. If your dose is different, do not change it unless your doctor tells you to do so.

The amount of medicine that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are using the medicine.

• For ophthalmic ointment dosage forms:
  • For mild to moderate infections:
    • Adults and children—Use every eight to twelve hours.
  • For severe infections:
    • Adults and children—Use every three to four hours until improvement occurs.
• For ophthalmic solution (eye drops) dosage forms:
  • For mild to moderate infections:
    • Adults and children—One drop every four hours.
  • For severe infections:
    • Adults and children—One drop every hour until improvement occurs.

Missed dose—

If you miss a dose of this medicine, take it as soon as possible. However, if it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not double doses.

Storage—

Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light. Keep from freezing.

Keep out of the reach of children.

Do not keep outdated medicine or medicine no longer needed.

Precautions While Using This Medicine:

If your eye infection does not improve within a few days, or if it becomes worse, check with your doctor.

Side Effects of This Medicine:

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.