Netilmicin

Pronunciation: net-il-MY-sin.

Generic name
Netilmicin (as netilmicin sulfate)
Drug class
Aminoglycoside antibiotic (semisynthetic, derived from sisomicin)
Form
Historical: injectable solution. Current (Canada): ophthalmic solution (netilmicin 0.3% + dexamethasone 0.1%, with and without preservative)
Route
Historically intravenous or intramuscular injection (systemic use); topical ophthalmic (eye drop) administration for the currently authorised Canadian combination product
Legal status
The historical systemic (injectable) form was not found in live regulator-database searches in the United States, United Kingdom, or Australia this session, consistent with independent secondary-source reporting that the US product (Netromycin) is off-market/discontinued. A real, currently authorised (2019) Canadian topical ophthalmic combination product (netilmicin + dexamethasone, NETILDEX) exists as a Health Canada-approved prescription product. Secondary/commercial sources (not independently regulator-verified this session) report the same combination product is also marketed in several other countries. New Zealand's regulatory status could not be directly verified this session.

Availability and supply rules vary by country

Trade names by country:

Australia: · Full directory

What Netilmicin (as netilmicin sulfate) is and how it works

Netilmicin is an aminoglycoside antibiotic, historically used as an injectable medicine for serious infections caused by gram-negative bacteria, including some infections resistant to gentamicin. Live searches of the official drug regulator databases in the United States, United Kingdom, and Australia found no current listing for this systemic form, consistent with independent reporting that the US product (Netromycin) has been discontinued -- this appears to be a genuine market withdrawal in these countries, not a gap in this page's research. Separately, a real, currently authorised topical eye-drop product combining netilmicin with the corticosteroid dexamethasone (NETILDEX) was approved in Canada in 2019 for treating eye inflammation where a bacterial infection is present or possible, and is reported (via secondary sources) to also be marketed in some other countries. (1) (5) (11)

If you have been told you are being considered for netilmicin, it matters a great deal which form is meant: the historical injectable antibiotic (largely unavailable in the countries checked here) or the Canadian eye-drop combination product. As with all aminoglycoside antibiotics, systemic netilmicin carries a real, well-documented risk of kidney damage and hearing/balance damage, which is why, historically, it required close monitoring with blood tests and sometimes hearing tests during treatment. The eye-drop combination product is a different, more localised use, though its own product information still warns about toxicity risk if the drug is absorbed into the body or combined with other aminoglycosides.

Mechanism of action: how Netilmicin (as netilmicin sulfate) works

Netilmicin, like other aminoglycosides, binds irreversibly to the bacterial 30S ribosomal subunit, causing misreading of the genetic code and inhibiting bacterial protein synthesis, which is bactericidal. It is not absorbed from the gastrointestinal tract, so systemic use requires injection. (9) (11)

What Netilmicin (as netilmicin sulfate) is used for

Serious gram-negative infections, including those resistant to gentamicin (historical systemic use)

Netilmicin was historically used by injection for serious infections caused by gram-negative bacteria, including strains resistant to gentamicin, such as septicaemia, complicated urinary tract infections, and respiratory or surgical-site infections in hospital settings. Live regulator searches found no current listing for this systemic use in the United States, United Kingdom, or Australia. (11) (1)

Inflammatory eye conditions with bacterial infection or risk of infection (current Canadian topical combination product)

In Canada, a netilmicin and dexamethasone combination eye-drop (NETILDEX) is currently authorised for inflammatory conditions of the front of the eye, including after eye surgery, where a bacterial infection is present or at risk. This is a topical, localised use, distinct from historical systemic antibiotic use. (5)

Before taking Netilmicin (as netilmicin sulfate)

Do not take / not appropriate for

  • Do not use any netilmicin-containing product if you have a known allergy to netilmicin or other aminoglycoside antibiotics. (all countries) (11)
  • Historical systemic netilmicin was contraindicated in myasthenia gravis, because aminoglycosides can worsen neuromuscular weakness. (historical systemic use) (11)
  • The Canadian eye-drop combination product is contraindicated in vaccinia, varicella, and other viral eye infections, and in hypersensitivity to aminoglycosides or corticosteroids. (Canada (ophthalmic combination product)) (5)

Tell your clinician about

  • Any history of kidney problems -- systemic aminoglycoside dosing depends heavily on kidney function.
  • Any existing hearing or balance problems before starting systemic treatment.
  • All other medicines you take, especially other antibiotics, diuretics, or medicines used during anaesthesia/surgery, because of real interaction and additive-toxicity risks.
  • Whether you are pregnant, planning pregnancy, or breastfeeding.
  • For the eye-drop product: any current eye infection type, since corticosteroid-containing eye drops are not suitable for certain viral or fungal eye infections.
(11) (5)

How to take Netilmicin (as netilmicin sulfate)

  • Historical systemic netilmicin was given only by injection (intravenous or intramuscular) in a hospital setting, with dosing individualised to body weight, age, and kidney function, and blood-level monitoring during treatment -- never a self-administered or self-adjusted medicine.
  • The current Canadian eye-drop combination product is administered as directed by an eye specialist or the product label -- follow the prescribing clinician's specific instructions rather than a generic schedule.
(11) (5)

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) (6) (9) (10) (11)

Missed dose

Systemic netilmicin was a hospital-administered medicine with clinician-managed timing, not a self-directed home dosing schedule. For the eye-drop combination product, contact the prescribing clinician or pharmacist for guidance on a missed application rather than guessing.

Overdose

Contact a doctor, pharmacist, or poison-control service promptly if excessive use is suspected, or if new hearing changes, ringing in the ears, dizziness, reduced urination, or unusual weakness or breathing difficulty occur -- these can be signs of aminoglycoside toxicity and need prompt clinical assessment. (11)

Side effects

Side effects and their urgency vary; report severe, persistent, or concerning symptoms.

For the eye-drop combination product: local eye irritation or discomfort has been reported.

What to notice: For the eye-drop combination product: local eye irritation or discomfort has been reported.

What to do: Discuss persistent or troublesome symptoms with the treating clinician or pharmacist. (5)

For historical systemic use: nephrotoxicity and ototoxicity were the most frequent and clinically significant adverse effects.

What to notice: For historical systemic use: nephrotoxicity and ototoxicity were the most frequent and clinically significant adverse effects.

What to do: Discuss persistent or troublesome symptoms with the treating clinician or pharmacist. (10)

Serious warnings

Signs of kidney damage — boxed_warning

Symptoms: Reduced urination, swelling, or unusual tiredness -- often detected first through blood tests rather than symptoms you would notice yourself.

Action: For systemic treatment, a care team monitors kidney function with regular blood tests. Report any reduced urination or new swelling promptly for assessment. A comparative clinical study found netilmicin's nephrotoxicity rate (21.3%) broadly similar to other aminoglycosides (gentamicin 18.6%, tobramycin 25%), so this is not a lesser risk within the class. (10)

Signs of hearing or balance damage — boxed_warning

Symptoms: Ringing in the ears (tinnitus), hearing loss, dizziness, or unsteadiness.

Action: Report any change in hearing or balance to a clinician immediately -- this damage is often irreversible, so early reporting matters. One comparative clinical study found netilmicin's ototoxicity incidence (2%) notably lower than gentamicin (18%), amikacin (12.9%), and tobramycin (11.5%) -- a genuine relative advantage specific to hearing/balance toxicity, not a reason to consider netilmicin risk-free, and it does not extend to the kidney-toxicity risk above. (10)

Signs of neuromuscular blockade or breathing difficulty — boxed_warning

Symptoms: Unusual muscle weakness or difficulty breathing, particularly around anaesthesia, surgery, or a large blood transfusion.

Action: Seek emergency medical help immediately if breathing difficulty occurs. This is a recognised, class-wide aminoglycoside risk, and is why netilmicin was historically contraindicated in myasthenia gravis. (11)

Confusing the historical systemic antibiotic with the current eye-drop combination product — high caution

Symptoms: Not applicable -- this is a product-identification safety point, not a symptom.

Action: Live regulator searches found no current systemic netilmicin product in the United States, United Kingdom, or Australia. If netilmicin is mentioned to you in one of these countries, confirm with a clinician or pharmacist exactly what product and form is meant, since a currently authorised product only exists (that this page could confirm) as a Canadian eye-drop combined with a corticosteroid. (1) (3) (4) (5)

Interactions

  • Other nephrotoxic or ototoxic medicines (e.g. vancomycin, certain cephalosporins, cyclosporine, furosemide, cisplatin, amphotericin): combining with netilmicin increases the risk of kidney or hearing/balance toxicity -- historically avoided or used only with careful monitoring. (11)
  • Non-depolarising muscle relaxants used during anaesthesia: netilmicin can enhance their effect, increasing the risk of prolonged muscle weakness/breathing difficulty. (11)
  • For the eye-drop combination product: combined topical and systemic aminoglycoside use raises the risk of additive toxicity -- disclose all other aminoglycoside use to a clinician. (5)

Pregnancy, breastfeeding, kidney/liver function, age

Pregnancy

No specific pregnancy safety data for netilmicin was independently verified this session; as an aminoglycoside, historical systemic use in pregnancy would require specialist risk-benefit assessment given the class-wide toxicity profile -- discuss with a clinician. (1) (2) (3) (4) (5) (6) (9) (10) (11)

Children

Historical systemic pediatric/neonatal dosing existed and was weight- and age-based (see dosing section), always clinician-directed with monitoring; the Canadian eye-drop combination product's pediatric use should be directed by the prescribing clinician. (1) (2) (3) (4) (5) (6) (9) (10) (11)

Elderly

No specific restriction identified in the sources reviewed beyond the general aminoglycoside need for careful renal-function-based dosing, which is especially relevant in older adults given higher rates of reduced kidney function. (1) (2) (3) (4) (5) (6) (9) (10) (11)

Renal_impairment

Significant dose reduction was required historically for systemic use, scaled to kidney function, with drug-level monitoring recommended -- this is a central, well-documented consideration for aminoglycosides generally. (1) (2) (3) (4) (5) (6) (9) (10) (11)

Monitoring

Before starting

  • Baseline kidney function testing
  • Baseline hearing assessment where systemic treatment is planned
  • Confirm which specific product/form (historical systemic vs. current ophthalmic combination) is actually being discussed

During treatment

  • For historical systemic use: regular kidney-function blood tests and, where available, hearing tests (audiograms), plus drug-level monitoring to guide dosing.
  • For the eye-drop combination product: watch for local irritation, and for signs of a secondary eye infection or worsening with prolonged use, per the product's own warnings.
(11) (5)

Storage

For the eye-drop combination product, store per the product label; historical systemic injectable formulations required clinician/pharmacy-controlled storage, not applicable to home use.

Professional information

Clinician-facing context only. Live regulator searches this session found no current systemic netilmicin product in the United States, United Kingdom, or Australia; this section reflects historical systemic clinical-reference dosing material alongside the real, currently authorised Canadian ophthalmic combination product's own monograph.

United States / United Kingdom / Australia

Indication: Not applicable -- no current product found in live regulator database searches this session.

Dose summary: Not applicable.

Renal context: Not applicable. (1) (3) (4)

Canada

Indication: Inflammatory ocular conditions of the anterior segment of the eye, with bacterial infection or its risk (ophthalmic combination product)

Dose summary: As directed by the prescribing eye specialist; product-specific instructions per the NETILDEX product monograph.

Renal context: Not applicable to the topical ophthalmic form; systemic absorption is a theoretical concern per the monograph's own warnings. (5)

Historical systemic use (clinical reference only, not a currently marketed product in the markets checked)

Indication: Serious gram-negative infections, including gentamicin-resistant strains

Dose summary: Weight- and age-based, renally adjusted; see dosing section for historical pediatric figures.

Renal context: Substantial dose reduction required for reduced kidney function, with drug-level monitoring. (11)

Mechanism of action

Hepatic guidance

No specific hepatic dose adjustment identified as necessary in the sources reviewed.

Overdose note

No specific antidote; manage suspected significant toxicity with supportive care, discontinuation, kidney-function and hearing assessment, and clinician or poison-control advice. (9) (11)

Frequently asked questions

Is netilmicin still available as an antibiotic injection?

Live searches of the official drug regulator databases in the United States, United Kingdom, and Australia found no current listing for the historical injectable form of netilmicin (marketed in the US as Netromycin), and an independent secondary clinical reference describes the US product as off-market/discontinued. This appears to be a genuine market withdrawal in these three countries. A real, currently authorised product does exist in Canada, but only as a topical eye-drop combined with a corticosteroid (NETILDEX), not the historical systemic injectable. (1) (2) (3) (4) (5)

What is NETILDEX and how is it different from the antibiotic injection?

NETILDEX is a Health Canada-approved (2019) eye-drop combining netilmicin with the corticosteroid dexamethasone, used for eye inflammation where a bacterial infection is present or possible. It is a topical, localised treatment for the eye, a materially different clinical context from the historical systemic (injected) antibiotic use of netilmicin, though its product information still warns about aminoglycoside toxicity risk if the drug is absorbed into the body or combined with other aminoglycosides. (5) (6)

Is netilmicin safer than other aminoglycoside antibiotics like gentamicin?

Genuinely mixed, and this page keeps the two toxicities distinct rather than blending them: one comparative clinical study found netilmicin's ototoxicity (hearing/balance damage) incidence markedly lower than gentamicin, amikacin, and tobramycin. However, the same study found netilmicin's nephrotoxicity (kidney damage) rate broadly similar to gentamicin and tobramycin -- so netilmicin is not simply 'the safer aminoglycoside' across the board; its comparative advantage in that evidence was specific to hearing/balance toxicity. (10)

What are the main risks of aminoglycoside antibiotics like netilmicin?

Aminoglycosides, including netilmicin, carry a real, well-documented risk of kidney damage (nephrotoxicity), damage to the nerve responsible for hearing and balance (ototoxicity, which is often permanent), and, less commonly, neuromuscular blockade causing muscle weakness or breathing difficulty, particularly around anaesthesia or surgery. This is why systemic use historically required close monitoring with blood tests and, where available, hearing tests. (10) (11)

What is the mechanism of action of Netilmicin (as netilmicin sulfate)?

Netilmicin, like other aminoglycosides, binds irreversibly to the bacterial 30S ribosomal subunit, causing misreading of the genetic code and inhibiting bacterial protein synthesis, which is bactericidal. It is not absorbed from the gastrointestinal tract, so systemic use requires injection. (9) (11)

What is the generic name of Netilmicin?

The generic name is Netilmicin (as netilmicin sulfate). (9) (5)

What class of drug is Netilmicin (as netilmicin sulfate)?

Netilmicin is classed as: Aminoglycoside antibiotic (semisynthetic, derived from sisomicin). (9) (5)

References

  1. DailyMed search for 'netilmicin' -- zero resultsDailyMed (U.S. National Library of Medicine) -- product label search · United States · accessed 2026-07-30 · source 1
  2. Netilmicin (Netromycin) -- Davis's Drug Guide entryDavis's Drug Guide (Nursing Central / F.A. Davis) -- secondary clinical reference · United States · accessed 2026-07-30 · source 2
  3. Medicines containing the active ingredient netilmicin / netilmicin sulfate -- zero productselectronic medicines compendium (emc), United Kingdom -- ingredient product listing · United Kingdom · accessed 2026-07-30 · source 3
  4. TGA PI & CMI search for 'netilmicin' -- zero documentsTherapeutic Goods Administration (TGA), Australia -- PI & CMI product search · Australia · accessed 2026-07-30 · source 4
  5. NETILDEX (netilmicin sulfate 0.3% + dexamethasone sodium phosphate 0.1%) ophthalmic solution -- Product MonographHealth Canada -- Product Monograph including Patient Medication Information · Canada · accessed 2026-07-30 · source 5
  6. Regulatory Decision Summary for Netildex (with Preservative), Netildex (without Preservative)Health Canada -- Drug and Health Products Portal, Regulatory Decision Summary · Canada · accessed 2026-07-30 · source 6
  7. NETILDEX marketing in Italy, Romania, and other countries -- secondary-source disclosuren/a -- secondary/commercial sources, not independently regulator-verified this session · European Union · accessed 2026-07-30 · source 7
  8. Medsafe product/trade-name search for 'netilmicin' -- form-based search, no direct result page capturedn/a -- disclosed live-query limitation, not a confirmed negative or positive result · New Zealand · accessed 2026-07-30 · source 8
  9. Netilmicin -- identity, history, and comparative safety backgroundWikipedia, cross-referencing the British National Formulary (BNF) and WHO Model List of Essential Medicines · General/international background · accessed 2026-07-30 · source 9
  10. Netilmicin: Clinical Efficacy, Tolerance, and ToxicityPeer-reviewed comparative clinical study, Antimicrobial Agents and Chemotherapy (American Society for Microbiology) · General/international clinical evidence · accessed 2026-07-30 · source 10
  11. Netilmicin -- mechanism, indication, contraindications, dosing, renal dose adjustmentPediatric Oncall -- clinical drug-index reference · General/international clinical reference · accessed 2026-07-30 · source 11

Brand names by country

Single-ingredient Netilmicin (as netilmicin sulfate) names are shown separately by country. Product availability, strengths, and supply rules can change; combination products are not included here.

Priority countries

View brands in additional countries.

This page provides general reference information about netilmicin and is not a substitute for advice from a pharmacist or doctor. Live regulator database searches found no current systemic netilmicin product in the United States, United Kingdom, or Australia -- this page includes historical systemic clinical-reference information for context alongside the real, currently authorised Canadian eye-drop combination product. As with all aminoglycoside antibiotics, systemic use carries a real risk of kidney and hearing/balance damage.

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