Tobramycin

Description

Tobramycin ophthalmic solution 0.3% is a sterile topical ophthalmic antibiotic formulation designed for the treatment of external ophthalmic infections. Each mL of this solution contains 0.3% tobramycin (3 mg) as the active ingredient. The formulation includes benzalkonium chloride as a preservative at a concentration of 0.01% (0.1 mg). Inactive ingredients consist of boric acid, sodium sulfate, sodium chloride, tyloxapol, sodium hydroxide and/or sulfuric acid (for pH adjustment), and water for injection. The pH of Tobramycin ophthalmic solution 0.3% ranges from 7.0 to 8.0, with an osmolality of 260-320 mOsm/kg. The molecular weight of tobramycin is 467.52, and its molecular formula is C18H37N5O9. The chemical name is 0-{3-amino-3-deoxy-α-D-gluco-pyranosyl (1→4)}-0-{2,6-diamino-2,3,6-trideoxy α-D-ribohexo-pyranosyl-(1→6)}-2 deoxystreptamine.

Uses and Indications

Tobramycin ophthalmic solution 0.3% is indicated for the treatment of external infections of the eye and its adnexa caused by susceptible bacteria. This topical antibiotic is effective in managing bacterial infections and is supported by clinical studies demonstrating its safety and efficacy in pediatric populations.

Appropriate monitoring of bacterial response to topical antibiotic therapy should accompany the use of tobramycin ophthalmic solution 0.3% to ensure optimal therapeutic outcomes.

Dosage and Administration

In cases of mild to moderate disease, the recommended dosage is to instill 1 or 2 drops into the affected eye(s) every 4 hours. For severe infections, the dosage is increased to 2 drops instilled into the eye(s) hourly until clinical improvement is observed. Following improvement, the frequency of administration should be gradually reduced before discontinuation of treatment.

Contraindications

Tobramycin ophthalmic solution 0.3% is contraindicated in patients with a known hypersensitivity to any of its components. Use in these patients may lead to severe allergic reactions.

Warnings and Precautions

Topical ophthalmic medications are intended solely for external use and must not be injected into the eye. Healthcare professionals should be aware that sensitivity to topically applied aminoglycosides, including tobramycin, may occur in some patients.

The severity of hypersensitivity reactions can range from localized effects to more generalized responses. These reactions may manifest as erythema, itching, urticaria, skin rash, or, in severe cases, anaphylaxis, anaphylactoid reactions, or bullous reactions.

In the event that a patient experiences a sensitivity reaction to tobramycin ophthalmic solution 0.3%, it is imperative to discontinue use immediately. Monitoring for signs of hypersensitivity is recommended to ensure patient safety and to facilitate timely intervention if adverse reactions occur.

Side Effects

Most patients treated with tobramycin ophthalmic solution 0.3% may experience hypersensitivity reactions, which can range from localized effects to more severe generalized reactions. Common localized ocular toxicities include lid itching and swelling, as well as conjunctival erythema, occurring in less than three of 100 patients.

Serious adverse reactions reported in postmarketing experience include anaphylactic reactions, Stevens-Johnson syndrome, and erythema multiforme. Additionally, patients receiving systemic aminoglycosides may experience neurotoxicity, ototoxicity, nephrotoxicity, and aggravation of muscle weakness, particularly in those with known or suspected neuromuscular disorders such as myasthenia gravis or Parkinson's disease.

Patients may also exhibit sensitivity to topically applied aminoglycosides, with reactions that can vary in severity. These reactions may include erythema, itching, urticaria, skin rash, and in severe cases, anaphylaxis or anaphylactoid reactions. If any hypersensitivity reaction occurs, it is advised to discontinue the use of tobramycin ophthalmic solution 0.3% and initiate appropriate therapy.

Prolonged use of this medication may lead to the overgrowth of nonsusceptible organisms, including fungi. In the event of a superinfection, appropriate therapeutic measures should be taken. Furthermore, cross-sensitivity to other aminoglycoside antibiotics may occur; therefore, if hypersensitivity develops with this product, it is essential to discontinue use and provide suitable treatment.

Drug Interactions

There are currently no documented drug interactions associated with this medication. Additionally, there is no information available regarding interactions with laboratory tests. As such, no specific recommendations for dosage adjustments or monitoring are warranted at this time.

Packaging & NDC

The table below lists all NDC Code configurations of Tobramycin, the U.S. brand-name prescription product. Columns show Packaging, Formulation Type, and Active Ingredient Strength.

Pediatric Use

Safety and effectiveness in pediatric patients below the age of 2 months have not been established. Clinical studies have demonstrated that tobramycin is safe and effective for use in children.

Geriatric Use

Elderly patients may not exhibit overall differences in safety or effectiveness when compared to younger patients. Therefore, no specific dosage adjustments are necessary based solely on age. However, it is essential for healthcare providers to consider the individual health status and comorbidities of geriatric patients when prescribing treatment. Regular monitoring and assessment of therapeutic response and potential adverse effects are recommended to ensure optimal care in this population.

Pregnancy

Reproduction studies in three types of animals at doses up to 33 times the normal human systemic dose have revealed no evidence of impaired fertility or harm to the fetus due to tobramycin. However, there are no adequate and well-controlled studies in pregnant women. Because animal studies are not always predictive of human response, tobramycin should be used during pregnancy only if clearly needed. Healthcare professionals are advised to weigh the potential benefits against the risks when considering the use of this medication in pregnant patients.

Lactation

Because of the potential for adverse reactions in nursing infants from tobramycin ophthalmic solution 0.3%, a decision should be made whether to discontinue nursing the infant or discontinue the drug, taking into account the importance of the drug to the mother.

Renal Impairment

Patients with renal impairment have not been specifically addressed in the available prescribing information. There are no dosage adjustments, special monitoring requirements, or safety considerations outlined for individuals with reduced kidney function. Healthcare professionals should exercise caution and consider the lack of data when prescribing to this patient population.

Hepatic Impairment

Patients with hepatic impairment have not been specifically studied in relation to the use of this medication. Consequently, there are no established dosage adjustments, special monitoring requirements, or precautions outlined for individuals with compromised liver function. It is recommended that healthcare providers exercise caution when prescribing this medication to patients with hepatic impairment, given the lack of data on its safety and efficacy in this population. Regular monitoring of liver function may be prudent in these cases, although specific parameters are not defined in the available information.

Overdosage

There is currently no specific information available regarding overdosage for this medication. In the absence of documented overdosage data, healthcare professionals are advised to monitor patients closely for any unusual symptoms or adverse effects that may arise following administration.

In the event of suspected overdosage, it is recommended that healthcare providers initiate supportive care and symptomatic treatment as necessary. Patients should be evaluated for potential complications, and appropriate interventions should be implemented based on the clinical presentation.

Healthcare professionals are encouraged to report any cases of suspected overdosage to the relevant authorities to contribute to the ongoing assessment of the medication's safety profile.

Nonclinical Toxicology

Reproduction studies conducted in three animal species at doses up to 33 times the normal human systemic dose have demonstrated no evidence of impaired fertility or teratogenic effects associated with tobramycin. However, it is important to note that there are no adequate and well-controlled studies in pregnant women. Due to the limitations of animal studies in predicting human responses, the use of this drug during pregnancy should be considered only when clearly necessary.

Postmarketing Experience

Postmarketing experience has identified additional adverse reactions associated with the use of the product. Reports include anaphylactic reactions, Stevens-Johnson syndrome, and erythema multiforme.

Furthermore, systemic aminoglycosides have been associated with neurotoxicity, ototoxicity, and nephrotoxicity in patients undergoing treatment. It has also been noted that aminoglycosides may exacerbate muscle weakness in individuals with known or suspected neuromuscular disorders, such as myasthenia gravis or Parkinson's disease, due to their potential impact on neuromuscular function.

Patient Counseling

Healthcare providers should advise patients to avoid touching the dropper tip to any surface, as this may lead to contamination of the solution. It is important to inform patients that they should not wear contact lenses if they exhibit signs and symptoms of a bacterial ocular infection.

Providers should discuss the potential risks associated with tobramycin ophthalmic solution 0.3% for nursing infants. A careful decision should be made regarding whether to discontinue nursing or the medication, weighing the importance of the drug to the mother against the potential for adverse reactions in the infant.

Additionally, healthcare providers should communicate that the safety and effectiveness of this medication in pediatric patients under the age of 2 months have not been established. If patients experience a sensitivity reaction to tobramycin ophthalmic solution 0.3%, they should be instructed to discontinue use and consult their healthcare provider.

Storage and Handling

Tobramycin ophthalmic solution 0.3% is supplied in a container that allows for easy dispensing. It should be stored at a temperature range of 2° to 25°C (36° to 77°F) to maintain its efficacy.

Once opened, the solution can be used until the expiration date indicated on the bottle. It is important to ensure that the container is properly sealed when not in use to prevent contamination and preserve the integrity of the product.

Additional Clinical Information

No further data are available.

FDA Insert (PDF)

This document is the official FDA-approved prescribing information for Tobramycin as submitted by Sportpharm LLC. It includes detailed information about indications, dosage, contraindications, warnings, and clinical pharmacology.

View full prescribing information (PDF)