tobramycin at a glance
Medicine class
Aminoglycoside antibiotic
Inhaled use
Chronic Pseudomonas lung infection in cystic fibrosis
Injection use
Serious infections caused by susceptible bacteria
Important checks
Kidney function, hearing and balance may require monitoring
What is tobramycin used for?
Licensed uses depend on the formulation.
Nebuliser solution and inhalation powder: chronic Pseudomonas aeruginosa lung infection in people with cystic fibrosis aged 6 years and older.
Injection: serious susceptible infections affecting the central nervous system, bloodstream, abdomen, urinary or lower respiratory tract, skin, bone or soft tissues, including burns.
Injection may be considered for selected serious staphylococcal infections when less toxic alternatives are unsuitable and susceptibility supports use.
Specialist services may use nebulised tobramycin outside its licence for Pseudomonas infection in non-cystic-fibrosis bronchiectasis.
How does tobramycin work?
Tobramycin binds to bacterial ribosomes and disrupts protein production, causing faulty proteins, damaging the cell envelope and killing susceptible bacteria. It is particularly active against aerobic Gram-negative organisms such as Pseudomonas aeruginosa.
tobramycin preparations and strengths
Inhaled preparation
Route: Inhaled
Strengths: 170 mg, 300 mg/5 mL
Capsule
Route: Oral
Strengths: 28 mg
Injection
Route: Parenteral
Strengths: 40 mg/mL
How to take tobramycin
Use only the formulation and device specified by the clinical team.
Nebuliser solution is for inhalation, not injection. Open the single-use container immediately before use, put its contents in the specified clean nebuliser and discard leftovers.
Sit or stand upright and breathe normally through the mouthpiece. Clean and disinfect personal nebuliser equipment as instructed.
Do not mix nebuliser solution with other inhaled medicines in the chamber.
Podhaler capsules must be inhaled using the Podhaler device and not swallowed. Keep them in the blister until use and check that each capsule is empty afterwards.
When using several respiratory treatments, inhaled tobramycin is generally used after bronchodilators, airway-clearance physiotherapy and other inhaled medicines.
Injection is given into a vein or muscle by a healthcare professional.
tobramycin side effects
Common or expected effects
- Inhaled powder: cough, productive cough, breathlessness, hoarse voice, throat or mouth pain, fever and coughing blood; altered taste, nausea, diarrhoea, wheeze and rash can also occur.
- Nebuliser solution: cough and hoarse voice.
- Injection: reported effects include nausea, vomiting, diarrhoea, headache, dizziness, rash, itching, fever and injection-site pain, although frequencies are uncertain.
Get urgent medical advice
- Allergic reaction or severe bronchospasm causing swelling, wheeze or breathing difficulty.
- Hearing loss, tinnitus or severe vertigo; hearing damage can sometimes be permanent.
- Reduced urine or abnormal kidney tests suggesting kidney injury.
- Neuromuscular blockade, worsening muscle weakness or respiratory paralysis, particularly with systemic exposure and interacting medicines.
- Significant haemoptysis or worsening respiratory symptoms during inhaled treatment.
tobramycin in pregnancy
Aminoglycosides may be used in pregnancy when treating the infection is judged more important than the potential risk. Inhaled exposure is low, but pregnancy data are limited. Injected aminoglycosides cross the placenta and carry a potential fetal hearing risk. Discuss pregnancy or plans to conceive promptly with the specialist or prescriber; do not stop essential treatment independently.
tobramycin while breastfeeding
Systemically administered tobramycin enters breast milk. Transfer after inhalation is expected to be much lower but is not well quantified. Advice differs by formulation, so the prescriber or a specialist breastfeeding medicines service should review the treatment need, route, infant age and infant health.
tobramycin interactions
The main concerns are added kidney, hearing and neuromuscular toxicity.
Furosemide, ethacrynic acid and other potent diuretics
May increase hearing or kidney toxicity; some formulations contraindicate or advise against concurrent use.
Amphotericin B, ciclosporin, tacrolimus and polymyxins
Concurrent or sequential use can increase kidney damage.
Common questions about tobramycin
Answers are fully visible for fast scanning and source review.
Is tobramycin a penicillin antibiotic?
No. It is an aminoglycoside. Allergy to another aminoglycoside remains important because cross-allergy can occur within the class.
Why are kidney tests needed?
Systemically absorbed tobramycin is cleared through the kidneys and can damage renal function. Impaired clearance can increase kidney and hearing toxicity.
What should I do if my ears start ringing?
Contact the treating team urgently. Tinnitus, new hearing difficulty or severe vertigo can be early signs of ototoxicity.
Sources
These sources were used to prepare and review this medicine page.
Prepared and reviewed by the iatroX editorial team.