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 g/mol, 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%. There are no reported teratogenic or nonteratogenic effects associated with this medication.

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 ensure that patients are aware of this critical instruction to prevent serious complications.

Patients may exhibit sensitivity to topically applied aminoglycosides, which can lead to a range of hypersensitivity reactions. These reactions may vary in severity, presenting as localized effects or more generalized symptoms, including erythema, itching, urticaria, skin rash, and 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. Continuous monitoring for any signs of hypersensitivity is recommended to ensure patient safety and to facilitate timely intervention if necessary.

Side Effects

The most frequent adverse reactions associated with tobramycin ophthalmic solution 0.3% include hypersensitivity and localized ocular toxicity, such as lid itching, swelling, and conjunctival erythema. These reactions are reported to occur in less than three out of 100 patients treated with the solution.

In addition to the common adverse reactions, post-marketing experience has identified several additional adverse reactions, including anaphylactic reactions, Stevens-Johnson syndrome, and erythema multiforme.

It is important to note that neurotoxicity, ototoxicity, and nephrotoxicity have been observed in patients receiving systemic aminoglycoside therapy. Furthermore, aminoglycosides may exacerbate muscle weakness in patients with known or suspected neuromuscular disorders, such as myasthenia gravis or Parkinson's disease, due to their potential effects on neuromuscular function.

Patients may also experience sensitivity to topically applied aminoglycosides, which can manifest as localized effects or generalized reactions. These reactions may include erythema, itching, urticaria, skin rash, and in severe cases, anaphylaxis or anaphylactoid reactions, including bullous reactions. If a sensitivity reaction to tobramycin ophthalmic solution 0.3% occurs, it is advised to discontinue use.

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 compared to younger patients when treated with this medication. However, it is essential for healthcare providers to remain vigilant in monitoring geriatric patients due to the potential for altered pharmacokinetics and increased sensitivity to medications in this population.

While specific dosage adjustments are not indicated based on age alone, clinicians should consider individual patient factors, including comorbidities and concurrent medications, when determining the appropriate treatment regimen for elderly patients. Regular assessment and monitoring are recommended to ensure optimal therapeutic outcomes and to mitigate any potential risks associated with treatment in this demographic.

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 drug 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 data regarding dosage adjustments, special monitoring, or safety considerations. Therefore, healthcare professionals should exercise caution when prescribing this medication to patients with reduced kidney function, as the lack of information necessitates careful clinical judgment and monitoring.

Hepatic Impairment

Patients with hepatic impairment have not been specifically studied in clinical trials for this medication. Consequently, there is no available information regarding dosage adjustments, special monitoring requirements, or precautions 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 warranted in these patients to ensure their safety while on treatment.

Overdosage

In the absence of specific overdosage information, it is essential for healthcare professionals to remain vigilant regarding the potential for overdose with this medication. In cases where an overdose is suspected, immediate medical attention should be sought.

Healthcare providers are advised to monitor patients closely for any signs or symptoms that may indicate an overdose. These may include, but are not limited to, altered mental status, cardiovascular instability, or gastrointestinal disturbances.

Management of an overdose should be guided by the clinical presentation of the patient. Supportive care is paramount, and symptomatic treatment should be initiated as necessary. It is recommended that healthcare professionals consult local poison control centers or toxicology experts for further guidance on the management of overdose cases.

In summary, while specific overdosage data is not available, healthcare professionals should exercise caution and be prepared to act swiftly in the event of an overdose, ensuring that appropriate interventions are implemented based on the patient's condition.

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, considering the importance of the drug to the mother.

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. Patients should be instructed to discontinue use if they experience any sensitivity reactions to tobramycin ophthalmic solution 0.3%.

Storage and Handling

Tobramycin ophthalmic solution 0.3% is supplied in a suitable container that ensures product integrity. 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, ensuring that proper handling and storage conditions are adhered to throughout its use.

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 REMEDYREPACK INC.. It includes detailed information about indications, dosage, contraindications, warnings, and clinical pharmacology.

View full prescribing information (PDF)