Tobramycin Antibiotic: Uses, Dosage, Side Effects & More

Summary of Key Points

Tobramycin is an antibiotic used to treat a variety of bacterial infections, including those affecting the respiratory and urinary tracts, as well as infections caused by Pseudomonas aeruginosa. It is available in several forms, such as eye drops, inhalation solutions, and injections. Tobramycin works by stopping the growth of bacteria. Always consult your healthcare provider before starting or adjusting your dose. You can also schedule a telemedicine visit with one of our providers for personalized care.

Names of Medication

US Brand Names: Tobi, Tobrex, Bethkis

Generic Name: Tobramycin

The generic name refers to the active ingredient, while the brand name is assigned by the manufacturer. The generic name is listed in parentheses.

Pharmacologic Category

Aminoglycoside Antibiotic

Tobramycin Dosage

Tobramycin is prescribed to treat various bacterial infections in adults. The dosage depends on the type and severity of the infection. Always follow your healthcare provider’s instructions and consult them before making any changes to your dose. You can also connect with one of our telemedicine providers for further guidance.

Tobramycin for Cystic Fibrosis

Inhalation Solution: 300 mg inhaled twice daily for 28 days, followed by 28 days off therapy.

Tobramycin for Eye Infections (Bacterial Keratitis)

Eye Drops: 1-2 drops in the affected eye every 4 hours. In severe cases, 2 drops every hour until improvement is noted.

Tobramycin for Pseudomonas Aeruginosa Infection

Inhalation Solution: 300 mg inhaled twice daily for 28 days, followed by 28 days off therapy.

Injection: 3-5 mg/kg/day intravenously (IV) or intramuscularly (IM) in divided doses every 8 hours.

Tobramycin for Respiratory Tract Infections

Injection: 3-5 mg/kg/day IV or IM in divided doses every 8 hours.

Tobramycin for Urinary Tract Infections (UTIs)

Injection: 3-5 mg/kg/day IV or IM in divided doses every 8 hours.

Tobramycin for Bone Infections

Injection: 3-5 mg/kg/day IV or IM in divided doses every 8 hours.

Tobramycin for Endocarditis

Injection: 3 mg/kg/day IV or IM in divided doses every 8 hours.

Tobramycin for Meningitis

Injection: 3-5 mg/kg/day IV or IM in divided doses every 8 hours.

Tobramycin for Septicemia

Injection: 3-5 mg/kg/day IV or IM in divided doses every 8 hours.

Tobramycin for Ear Infections (Otitis Media)

Ear Drops: 4 drops in the affected ear(s) 3-4 times daily.

Dosage Forms and Strengths

Inhalation Solution: 300 mg/5 mL

Eye Drops: 0.3% solution

Injection: 40 mg/mL, 80 mg/2 mL, 120 mg/3 mL

Ear Drops: 0.3% solution

How to Use Tobramycin: Administration Instructions

Always follow your healthcare provider’s instructions when using Tobramycin. Depending on the form prescribed, you may need to inhale it, apply it to your eyes or ears, or receive it through an injection. Be sure to complete the full course of treatment, even if you start feeling better before it’s finished. If you have any questions about how to use Tobramycin, schedule a telemedicine appointment with one of our providers for personalized guidance.

Contraindications for Tobramycin

A contraindication is a specific condition or situation where a drug should not be used because it may cause harm. If you have any of the following conditions, you should avoid Tobramycin or use it with extreme caution under the guidance of a healthcare provider.

Allergy to Tobramycin or other Aminoglycosides: If you have had an allergic reaction to Tobramycin or other aminoglycoside antibiotics (such as gentamicin or amikacin), you should not take this medication. Allergic reactions can range from mild skin rashes to severe anaphylaxis, a life-threatening condition.

Myasthenia Gravis: Tobramycin can worsen muscle weakness in individuals with myasthenia gravis, a condition that affects the muscles and nerves. This is because Tobramycin can interfere with nerve signals that control muscle movement.

Kidney Disease: Tobramycin is primarily processed by the kidneys. If you have kidney disease or reduced kidney function, taking Tobramycin can lead to toxic levels of the drug in your body, potentially causing serious side effects, including kidney damage.

Hearing Loss or Ear Problems: Tobramycin can cause ototoxicity (damage to the ear), which may result in hearing loss or balance issues. If you already have hearing problems or a history of ear conditions, avoid this medication unless your doctor determines that the benefits outweigh the risks.

Drug Interactions with Tobramycin

Tobramycin can interact with other medications, increasing the risk of side effects or reducing the effectiveness of treatment. Be sure to inform your healthcare provider about all medications you are taking, including over-the-counter drugs and supplements. Key drug interactions include:

Loop Diuretics: (furosemide [Lasix], bumetanide [Bumex]) – These medications can increase the risk of hearing loss when taken with Tobramycin.

Other Aminoglycosides: (gentamicin, amikacin) – Taking multiple aminoglycosides increases the risk of kidney damage and hearing loss.

Nonsteroidal Anti-Inflammatory Drugs (NSAIDs): (ibuprofen [Advil], naproxen [Aleve]) – These drugs can increase the risk of kidney damage when used with Tobramycin.

Vancomycin: (Vancocin) – Combining Tobramycin with vancomycin can increase the risk of kidney damage and hearing loss.

Cisplatin: (Platinol) – This chemotherapy drug can increase the risk of kidney damage and hearing loss when used with Tobramycin.

Tobramycin in Pregnancy

Is it safe to take Tobramycin when pregnant? Tobramycin is classified as a Category D medication by the FDA, which means there is evidence of potential risk to the fetus based on human studies. However, in certain situations, the benefits of using Tobramycin may outweigh the risks, particularly if the infection is severe and other antibiotics are not effective. If you are pregnant or planning to become pregnant, it is crucial to discuss the risks and benefits with your healthcare provider before starting Tobramycin. Our telemedicine providers are available to help you make an informed decision.

Tobramycin while Breastfeeding

Is it safe to take Tobramycin while breastfeeding? Tobramycin is excreted in breast milk in small amounts. While the risk to a nursing infant is generally considered low, potential side effects may include diarrhea, yeast infections, or allergic reactions. If you are breastfeeding, it’s important to carefully weigh the benefits of treating your infection with Tobramycin against the potential risks to your baby. Consult with one of our telemedicine providers to discuss your options and make the best choice for both you and your child.

Estimated Cost of Tobramycin

The cost of a 30-day supply of Tobramycin without insurance can vary depending on the form (e.g., Tobramycin eye drops, inhalation solution, or injectable). With a GoodRX coupon, Tobramycin eye drops (0.3%, 5 mL) typically range from $15 to $30. Prices for inhalation solutions or injectable forms may be higher, ranging from $50 to $200. For the most accurate pricing, check with your local pharmacy.

Possible Alternatives to Tobramycin

If Tobramycin is not suitable for you, or if you are looking for alternative treatments, there are other options available depending on the condition being treated. Always consult your healthcare provider before making any changes to your treatment plan. Our telemedicine providers are here to assist you in exploring the best alternatives.

Alternatives for Specific Conditions

1. Cystic Fibrosis: Inhaled antibiotics such as aztreonam (Cayston) or colistin may be alternatives. Regular chest physiotherapy and exercise can also help improve lung function.
2. Bacterial Keratitis: Fluoroquinolone eye drops like moxifloxacin (Vigamox) or gatifloxacin (Zymaxid) may be used. Practicing good eye hygiene and avoiding overuse of contact lenses can help prevent future infections.
3. Pseudomonas Aeruginosa Infection: Ceftazidime (Fortaz) or piperacillin-tazobactam (Zosyn) are potential alternatives. Proper wound care and hygiene are essential in preventing infections.
4. Respiratory Tract Infections: Alternatives include azithromycin (Zithromax) or levofloxacin (Levaquin). Staying hydrated, using a humidifier, and avoiding smoking can support respiratory health.
5. Urinary Tract Infections: Nitrofurantoin (Macrobid) or trimethoprim-sulfamethoxazole (Bactrim) may be used. Drinking plenty of water and urinating frequently can help flush bacteria from the urinary tract.
6. Bone Infections: Linezolid (Zyvox) or clindamycin (Cleocin) may be alternatives. Good nutrition and following a physical therapy plan can support recovery.
7. Endocarditis: Vancomycin or ceftriaxone (Rocephin) may be used. Maintaining good oral hygiene and scheduling regular dental checkups can help prevent bacterial infections that may lead to endocarditis.
8. Meningitis: Ceftriaxone (Rocephin) or meropenem (Merrem) may be alternatives. Vaccination and avoiding close contact with infected individuals can help reduce the risk of meningitis.
9. Septicemia: Piperacillin-tazobactam (Zosyn) or meropenem (Merrem) may be alternatives. Early treatment of infections and maintaining a strong immune system can help prevent septicemia.
10. Otitis Media: Amoxicillin (Amoxil) or cefdinir (Omnicef) may be used. Keeping the ears dry and avoiding exposure to smoke can help prevent ear infections.

Recent Updates on Tobramycin Research

Recent studies have focused on developing new Tobramycin formulations to enhance its effectiveness while minimizing side effects. For instance, researchers are investigating liposomal Tobramycin, which delivers the drug more directly to the lungs in cystic fibrosis patients, potentially reducing the risk of kidney and ear toxicity. Additionally, ongoing research is exploring the use of Tobramycin in combination with other antibiotics to combat antibiotic-resistant bacteria, such as Pseudomonas aeruginosa. These advancements may lead to more effective treatments with fewer side effects in the future.

Staying informed about the latest research is important. Be sure to discuss any new treatment options with your healthcare provider. If you have questions about your current treatment plan or want to explore alternatives, our telemedicine providers are here to help you make the best decision for your health.

James Kingsley

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