Tobramycin

Pronunciation: toe-bra-MY-sin.

Generic name: tobramycin
Drug class: Aminoglycoside antibacterial
Form: Solution for injection (e.g., 40 mg/mL vials)
Route: Intravenous injection; intramuscular injection also possible in certain regions
Legal status: Prescription-only medicine

Availability and supply rules vary by country

Trade names by country: United States · United Kingdom · Canada

What tobramycin is and how it works

Tobramycin is an aminoglycoside antibacterial used in serious susceptible bacterial infections. Systemic (injectable) formulations are for life- or function-threatening infections; inhaled and ophthalmic formulations have separate, specific approved uses and are not interchangeable with systemic injection. (1) (2) (3)

Tobramycin is a prescription-only medicine that is selected, dosed, and monitored by a specialist team. It is not for viral infections or for unconfirmed bacterial infections. Systemic therapy requires renal function and drug-level monitoring due to risks of kidney damage, hearing loss, and neuromuscular effects.

Mechanism of action: how tobramycin works

Tobramycin is a bactericidal aminoglycoside that inhibits bacterial protein synthesis. It is active against susceptible aerobic Gram-negative organisms and some staphylococci, with low activity against most Gram-positive organisms. Cross-resistance among aminoglycosides depends substantially on bacterial inactivating enzymes. (1) (3)

What tobramycin is used for

Serious susceptible infections (injection)

Tobramycin for injection is used for life- or function-threatening infections caused by susceptible aerobic Gram-negative organisms (such as Pseudomonas aeruginosa, Escherichia coli, Klebsiella, Enterobacter, Proteus, Citrobacter, and Serratia species) and some susceptible staphylococci. Sites of infection may include the central nervous system, bloodstream/sepsis, peritoneum, urinary tract, lower respiratory tract, skin, bone, soft tissue, and burns. It may be considered for serious staphylococcal infection when other antibacterials are unsuitable. Susceptibility testing guides use. (1) (2) (3)

Chronic pulmonary Pseudomonas aeruginosa infection in cystic fibrosis (inhaled formulation)

Inhaled (nebulised) tobramycin is used for chronic lung infection with Pseudomonas aeruginosa in people with cystic fibrosis, as per the specific product information. This use is formulation-specific and must not be administered by injection. (4)

Before taking tobramycin

Do not take / not appropriate for

Do not receive tobramycin if you have had a severe hypersensitivity reaction to tobramycin, any aminoglycoside, or a product excipient (such as sodium metabisulfite in some UK products) unless the responsible specialist determines otherwise. (all products) (3)
Do not administer tobramycin solution for injection into the spinal canal (intrathecal administration is contraindicated). (injection) (3)

Tell your clinician about

Any kidney problems, hearing loss, tinnitus, dizziness, or balance disorders.
A history of myasthenia gravis, Parkinson disease, or other neuromuscular condition.
Current or planned pregnancy, or if you are breastfeeding.
Dehydration, recent use of diuretics (especially ethacrynic acid or furosemide), or use of other nephrotoxic or ototoxic medicines (e.g., amphotericin B, certain cephalosporins).
Any previous allergic reaction to an aminoglycoside, sulfites, or any medicine.
Whether you are receiving neuromuscular-blocking agents or other antibacterials.

(1) (2) (3)

How to take tobramycin

Tobramycin injection is administered by a healthcare professional into a vein (IV) or muscle (IM) according to the product and local protocol.
The exact dose, frequency, and duration are based on the infection, body weight, renal function, and serum concentration monitoring.
Treatment is given in a monitored setting; self-administration is not applicable.
Do not alter the prescribed infusion rate or volume. If you have concerns about the administration, speak to the treating clinician.

(1) (2) (3)

Procedures and treatment changes

Tell the treating team before surgery, procedures, or any medicine change. Do not alter treatment without the responsible clinician. (1) (2) (3) (4) (5)

Missed dose

Missed doses of tobramycin injection are managed by the treating team. Contact the medical or nursing staff if you believe a scheduled dose has been delayed or missed; do not attempt to take a dose at home.

Overdose

If an overdose is suspected (e.g., too large a dose, fast injection, or excessive total exposure), the clinical team will manage it. Signs may include worsening kidney function, hearing loss, balance disturbance, or muscle weakness/respiratory difficulty. In a setting where accidental self-administration or a dosing error is identified, seek emergency medical attention and provide details of the product and estimated amount. (1) (3)

Side effects

The most important side effects of systemic tobramycin involve the kidneys, ears, and neuromuscular system. Risk increases with high doses, prolonged therapy, pre-existing impairment, and other risk factors.

Injection-site reaction

What to notice: Pain, redness, or swelling at the intravenous or intramuscular site.

What to do: Tell the nurse or doctor if it is bothersome or worsening. (1) (2)

Change in kidney function

What to notice: This is often first detected through laboratory monitoring (e.g., rising creatinine, reduced urine output). Symptoms such as swelling or fatigue may appear later.

What to do: The treating team will monitor kidney function regularly. Report any new symptoms to the team. (1) (3)

Hearing or balance changes

What to notice: Ringing in the ears (tinnitus), difficulty hearing, dizziness, vertigo, or unsteadiness.

What to do: Report immediately to the treating team. Hearing changes may be irreversible. (1) (3)

Worsening or new kidney problems

What to notice: Markedly decreased urine output, swelling, confusion, or significant changes in blood test results.

What to do: Seek prompt clinical assessment. (1) (3)

New or worsening hearing loss or tinnitus

What to notice: Sudden hearing loss, persistent ringing, or difficulty understanding speech.

What to do: Contact the treating clinician immediately; audiometry may be indicated. (1) (3)

Muscle weakness or breathing difficulty

What to notice: Unusual muscle weakness, drooping eyelids, difficulty speaking or swallowing, or feeling unable to breathe.

What to do: Seek emergency medical attention immediately. (1) (3)

Allergic reaction

What to notice: Rash, itching, swelling of the face or throat, severe wheezing, or breathlessness (may be related to sodium metabisulfite in some products).

What to do: Seek emergency care if symptoms are severe or rapidly worsening. (3)

Serious warnings

Neuromuscular blockade or respiratory paralysis — emergency

Symptoms: Muscle weakness, difficulty breathing, drooping eyelids, inability to speak or swallow, or respiratory distress.

Action: Call emergency services immediately. This can occur especially with rapid IV administration or in people with neuromuscular disorders. (1) (3)

Serious kidney injury — serious

Symptoms: Markedly reduced urine output, blood in urine, swelling, confusion, or significantly abnormal kidney function tests.

Action: Prompt medical assessment is needed. The treating team will adjust therapy based on renal function and drug-level monitoring. (1) (3)

Hearing loss or balance disorder — serious

Symptoms: Sudden hearing loss, persistent tinnitus, dizziness, vertigo, or unsteadiness.

Action: Contact the treating clinician immediately. Changes may be irreversible and can occur even after therapy has finished. (1) (3)

Fetal harm — warning

Symptoms: Aminoglycosides can cause fetal harm. A pregnancy status check and risk-benefit discussion should precede therapy.

Action: If you are pregnant or become pregnant, inform your clinician. Do not stop treatment without prescriber advice; uncontrolled serious infection also carries risks. (1)

Interactions

Medicine or test	Effect	Action
Loop diuretics (e.g., ethacrynic acid, furosemide)	May increase the risk of ototoxicity or alter tobramycin concentrations.	Ensure the prescriber is aware of all diuretic use; additional hearing monitoring may be indicated. (3)
Other nephrotoxic or ototoxic medicines (e.g., amphotericin B, certain cephalosporins)	Additive kidney or ear damage risk.	Give the specialist and pharmacist a complete medicine list; renal and auditory monitoring will be intensified. (3)
Neuromuscular-blocking agents	Prolonged neuromuscular blockade and risk of respiratory weakness.	The anaesthesia and critical care team must coordinate use and monitor respiratory function closely. (1) (3)
Beta-lactam antibacterials (e.g., certain penicillins, cephalosporins)	In-vitro inactivation can occur if mixed in the same infusion; clinically significant interactions may also happen in patients with reduced renal function.	These agents must be administered separately according to compatibility guidance; serum drug levels should be monitored. (3)

Pregnancy, breastfeeding, kidney/liver function, age

Premature and young neonatal infants

Renal immaturity prolongs tobramycin elimination, increasing toxicity risk. Dosing and monitoring are tailored to gestational and postnatal age, renal function, and serum concentrations; specialist paediatric input is essential. (3)

People with neuromuscular disorders

Conditions such as myasthenia gravis, Parkinson disease, or other neuromuscular disorders increase the risk of severe neuromuscular blockade and respiratory compromise. Careful assessment and monitoring are required. (3)

Older adults and people with renal impairment

Age-related decline in kidney function and pre-existing renal impairment increase nephrotoxicity and ototoxicity risk. Dosing adjustments, serial renal monitoring, and drug-level monitoring are necessary. Maintain adequate hydration. (1) (3)

Pregnancy and breastfeeding

Aminoglycosides can cause fetal harm. Use during pregnancy requires a thorough risk-benefit evaluation by the specialist; uncontrolled severe infection also poses maternal and fetal risks. Small amounts may pass into breast milk; clinical decision should balance infant risk against maternal treatment need. (1) (3)

Monitoring

Before starting

Confirm the infection site, severity, and microbiological culture and susceptibility results.
Assess baseline renal function (e.g., serum creatinine, estimated creatinine clearance), hydration status, and urine output.
Evaluate auditory and vestibular function if risk factors are present (pre-existing impairment, prolonged treatment, co-administration of ototoxic drugs).
Review for contraindications: hypersensitivity to tobramycin, aminoglycosides, or excipients; intrathecal route is contraindicated.
Check pregnancy status in individuals of childbearing potential.

During treatment

Monitor renal function at regular intervals, more frequently if impaired or in at-risk populations.
Measure serum tobramycin concentrations (peak and trough) to guide dosing and minimise toxicity risk.
Assess for signs of ototoxicity: tinnitus, subjective hearing loss, dizziness, vertigo. Audiometry may be indicated.
Observe for neuromuscular weakness, especially after rapid IV administration or in predisposed patients.
Watch for allergic reactions (including those related to sodium metabisulfite in some UK products).
Screen for superinfection or overgrowth of non-susceptible organisms.

(1) (2) (3)

Storage

Tobramycin injection solution must be stored according to the specific product's instructions, typically at controlled room temperature and protected from light and heat. Unused portions should be discarded. The healthcare facility manages storage conditions; patients should not handle or store injection products at home.

Professional information

Clinician-facing context only. Use the current local product information, formal susceptibility data, and infection-site and renal-function specifics to determine dosing.

All regions

Indication: Serious susceptible infection (injection)

Dose summary: No universal dose is displayed. Dose, frequency, and duration must be individualised based on the exact product, infection site/severity, body weight, renal function, and serum concentration monitoring. The current local label and formal institutional protocols must be followed.

Renal context: Reduced renal clearance requires dose adjustment and intensive pharmacokinetic monitoring. Do not infer a web-based adjustment; use local product information and specialist pharmacokinetic guidance. (1) (3)

Mechanism of action

Hepatic guidance

Hepatic impairment is not a primary determinant of tobramycin dosing; renal function is the critical parameter. Use specialist judgement.

Overdose note

Suspected overdose requires product identification, dose reconstruction, immediate assessment of renal function, serum drug levels, auditory and vestibular evaluation, and supportive care. Haemodialysis may be considered. (1) (3)

Frequently asked questions

What is tobramycin?

Tobramycin is an aminoglycoside antibacterial available in distinct systemic (injectable), inhaled, and ophthalmic formulations. The formulation determines the approved use and administration route; they are not interchangeable. (1) (3) (4)

Why are kidney and hearing checks important with systemic tobramycin?

Systemic tobramycin can damage the kidneys and the inner ear (causing hearing loss or balance problems). These effects can be irreversible and are more likely with high or prolonged exposure, pre-existing kidney problems, or other risk factors. Monitoring helps the team adjust therapy and reduce risk. (1) (3)

Are tobramycin injection, nebuliser solution, and eye drops interchangeable?

No. They are formulation-specific products with different routes, concentrations, and approved uses. A systemic injection must never be inhaled or used in the eye, and vice versa. Only the prescribed product should be used in exactly the way directed. (3) (4)

Why might blood concentrations be monitored during systemic therapy?

Tobramycin is cleared mainly by the kidneys and can accumulate to toxic levels if kidney function is reduced. Measuring blood levels helps the clinical team keep the drug within a range that is effective but less likely to cause kidney or ear damage. (3)

Does tobramycin treat viral infections?

No. All regulatory labels state that tobramycin is for proven or strongly suspected susceptible bacterial infections. It has no activity against viruses and should not be used for colds, flu, or other viral illnesses. (1) (3)

What is the mechanism of action of tobramycin?

What is the generic name of Tobramycin?

The generic name is tobramycin. (1) (2) (3)

What class of drug is tobramycin?

Tobramycin is classed as: Aminoglycoside antibacterial. (1) (2) (3)

References

Tobramycin for Injection — prescribing informationU.S. Food and Drug Administration via DailyMed · United States · dated 2024-01-15 · accessed 2026-08-11 · source 1
Tobramycin Injection USP — prescribing informationU.S. Food and Drug Administration via DailyMed · United States · dated 2026-04-13 · accessed 2026-08-11 · source 2
Tobramycin 40 mg/mL Solution for Injection — Summary of Product Characteristicselectronic Medicines Compendium (UK) · United Kingdom · dated 2026-06-25 · accessed 2026-08-11 · source 3
Tobramycin 300 mg/5 mL Nebuliser Solution — Summary of Product Characteristicselectronic Medicines Compendium (UK) · United Kingdom · dated 2025-10-07 · accessed 2026-08-11 · source 4
Tobramycin Injection USP — product informationHealth Canada Drug Product Database · Canada · accessed 2026-08-11 · source 5

Brand names by country

Single-ingredient tobramycin names are shown separately by country. Product availability, strengths, and supply rules can change; combination products are not included here.

Priority countries

United States

TOBI300 mg/5mL · viatris specialty llc
TOBI Podhaler28 mg · viatris specialty llc
Tobramycin Inhalation Solution Pak300 mg/5mL · genericus, inc.
Kitabis Pak300 mg/5mL · pari respiratory equipment, inc.
BETHKIS300 mg/4mL · chiesi usa, inc.
TOBREX3 mg/g · novartis pharmaceuticals corporation

United Kingdom

Tobramycin 40 mg/mL Solution for Injectioncurrent licensed product · 40 mg/mL · See current UK SmPC for marketing authorisation holder

Canada

TOBREX
TOBI
TOBRAMYCIN
TOBI PODHALER

View brands in additional countries.