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Topical ophthalmic (steroid + aminoglycoside) Pregnancy: No clinical data are available referred to Netildex use in pregnant women. Studies in animals have shown teratogen activity for dexamethasone. It is preferable to avoid the use of Netildex during pregnancy. Breastfeeding: there is insufficient information on the excretion of dexamethasone or netilmicin or their metabolites in human milk following ocular use. A risk to the newborns/infants cannot be excluded. Netildex should not be used during breastfeeding. Fertility: there is no available data on the effect of Netildex on human fertility. (UK SPC §4.6)

Dexamethasone with netilmicin

Brand names: specials

This combined ophthalmic preparation contains the corticosteroid dexamethasone with the aminoglycoside antibiotic netilmicin, used for inflammatory eye conditions where a susceptible bacterial infection is present or likely.

Adult dose

Dose: Inflammatory ocular conditions of the anterior segment of the eye, including post-operative cases, where bacterial infection or a risk of bacterial infection with netilmicin-susceptible microorganisms exists: adults (including the elderly) instil 1 drop into the conjunctival sac four times a day in each affected eye, or according to medical prescription. Product: netilmicin 3 mg/ml + dexamethasone 1 mg/ml eye drops, solution (each ml contains netilmicin sulphate 4.55 mg equivalent to netilmicin 3 mg, and dexamethasone disodium phosphate 1.32 mg equivalent to dexamethasone 1 mg)
Route: Ophthalmic (eye drops into the conjunctival sac) - for ophthalmic use only
Frequency: Four times a day in each affected eye (or according to medical prescription)
Product: UK SPC via MHRA Products - NETILMICIN/DEXAMETHASONE 3 MG/ML + 1 MG/ML EYE DROPS SOLUTION (PLGB539410017), SIFI Pharmaceuticals Limited (named 'Netildex' in the SPC text). COVERAGE: this SPC covers the 3 mg/ml + 1 mg/ml licensed eye drops only; any other strength or unlicensed 'special' preparation is not covered. §4.1 (verbatim): 'indicated for the treatment of inflammatory ocular conditions of the anterior segment of the eye, including post-operative cases, where bacterial infection or a risk of bacterial infection with netilmicin-susceptible microorganisms exists. When prescribing Netildex, consideration should be given to official guidance on the appropriate use of antibacterial agents.' VERBATIM §4.2: 'Adults (including the elderly) Instill 1 drop into the conjunctival sac four times a day in each affected eye or according to medical prescription.' DURATION (§4.2, verbatim): 'The usual treatment duration can vary from 5 to 14 days.' The SPC prints no maximum dose. ADMINISTRATION (§4.2): 'When using nasolacrimal occlusion or closing the eyelids for 2 minutes, systemic absorption is reduced. This may result in a decrease of systemic side effects and an increase in local activity.' Contact lenses should not be worn during treatment with corticosteroid eye drops; if worn they should be removed before instillation and may be reinserted after 15 minutes. If more than one topical ophthalmic drug is being used, the drugs should be administered at least ten minutes apart; eye ointments should be placed last. SAFETY (§4.4): intraocular pressure should be routinely monitored in case of treatment lasting longer than 15 days; if significant clinical improvement is not reported within a few days, or any irritation or sensitization occurs, discontinue treatment and start adequate therapy. Not to be given orally or introduced into the anterior chamber. CHILDREN (no paediatric dose is written): §4.2 'The safety and efficacy of Netildex in children and adolescents less than 18 years of age has not yet been established. No data is available. The product should be administered in paediatric patients only after a careful benefit-risk assessment and strict medical control'; §4.4 'Netildex is not recommended for use in children and adolescents'. The old openFDA record in this bundle (systemic dexamethasone alone) was not used.

Dose adjustments

Renal

No renal dose adjustment is printed in the retrieved SPC sections. §4.5 (netilmicin): concomitant administration of other potentially nephrotoxic and ototoxic antibiotics (even topically, particularly if intracavitary) may increase the risk of these effects.

Hepatic

No hepatic dose adjustment is printed in the retrieved SPC sections.

Dose independently re-sourced from UK Summary of Product Characteristics (SPC) via MHRA Products — clinician-reviewed. Always confirm against the product SmPC and your local formulary before prescribing.

Contraindications

  • Hypersensitivity to the active substances, to aminoglycoside antibiotics or to any of the excipients listed in section 6.1 (§4.3)
  • Intraocular hypertension (§4.3, corticosteroid-related)
  • Herpetic keratitis or other ocular infections caused by herpes simplex (§4.3)
  • Viral diseases of the cornea and of the conjunctiva (§4.3)
  • Ocular fungal diseases (§4.3)
  • Mycobacterial ocular infections (§4.3)

Side effects

  • Eye disorders (frequency not known): intraocular pressure increased (after 15-20 days of topical administration in susceptible or glaucomatous patients), posterior subcapsular cataract formation, blurred vision, occurrence or worsening of Herpes simplex or fungal infections, impaired healing (§4.8)
  • Immune system disorders: ocular hypersensitivity - conjunctival hyperaemia, burning, itching (§4.8)
  • Endocrine disorders: Cushing's syndrome, adrenal suppression (§4.8, §4.4)
  • Corneal calcification has been reported very rarely with phosphate-containing eye drops in some patients with significantly damaged corneas (§4.8)
  • Benzalkonium chloride (preservative) has been reported to cause eye irritation, symptoms of dry eyes and may affect the tear film and corneal surface (§4.8)
  • Prolonged corticosteroid use may result in ocular hypertension/glaucoma with optic nerve damage, posterior subcapsular cataract, delayed wound healing and increased hazard of secondary ocular infection; in thinning of the cornea or sclera perforation has been reported with topical steroids (§4.4)

Interactions

  • Other potentially nephrotoxic and ototoxic antibiotics (even topically, particularly if intracavitary) may increase the risk of nephrotoxicity and ototoxicity (§4.5)
  • Cisplatin, polymyxin B, colistin, viomycin, streptomycin, vancomycin, other aminoglycosides, some cephalosporins (cephaloridine) or potent diuretics such as ethacrynic acid and furosemide: concomitant or subsequent administration with netilmicin should be avoided (§4.5)
  • Beta-lactam antibiotics (penicillins or cephalosporins): in vitro, mutual inactivation with an aminoglycoside may occur (§4.5)
  • Anticholinergics, especially atropine and related compounds: risk of increased intraocular pressure with prolonged corticosteroid therapy in patients predisposed to acute angle closure (§4.5)
  • CYP3A4 inhibitors (including ritonavir and cobicistat): may decrease dexamethasone clearance, with adrenal suppression/Cushing's syndrome; avoid unless the benefit outweighs the risk (§4.4, §4.5)
  • Other phosphate-containing eye medications: increased risk of corneal deposits or opacity, especially with a compromised cornea (§4.4, §4.5)

Monitoring

  • Intraocular pressure should be routinely monitored in case of treatment lasting longer than 15 days (§4.4)
  • If significant clinical improvement is not reported within a few days, or any irritation or sensitization occurs, discontinue treatment and start adequate therapy (§4.4)
  • Visual disturbance (blurred vision) with topical corticosteroids: consider referral to an ophthalmologist to evaluate causes such as cataract, glaucoma or central serous chorioretinopathy (§4.4)
  • Patients on CYP3A4 inhibitors should be monitored for systemic corticosteroid side-effects (§4.4)
  • Use with caution in dry eye patients and where the cornea may be compromised; close monitoring in frequent or prolonged use (benzalkonium chloride) (§4.4)
  • In acute purulent infections of the eye corticosteroids may mask or exacerbate infection (§4.4)

Clinical monograph

How it works

Dexamethasone dampens ocular inflammation by inhibiting inflammatory mediators, while netilmicin binds the bacterial 30S ribosomal subunit to inhibit protein synthesis, giving bactericidal activity against many Gram-negative and some Gram-positive organisms.

Prescribing in practice

  • Topical corticosteroids are contraindicated in undiagnosed red eye and suspected herpes simplex (dendritic) keratitis because of the risk of corneal melt and perforation, so a herpetic cause must be excluded.
  • Prolonged use carries the risk of steroid-induced glaucoma, cataract and masking of infection, so courses should be short and ophthalmologist-led.
  • Aminoglycosides can cause local hypersensitivity and surface toxicity; discontinue if irritation or allergy develops.

Monitoring

With more than brief use, monitor intraocular pressure and review the cornea and treatment response, stopping if infection worsens or hypersensitivity occurs.

Counselling the patient

  • Use only for the prescribed short course and do not self-restart for later eye symptoms.
  • Seek advice if the eye becomes more painful, red or swollen.
  • Remove contact lenses during treatment unless advised otherwise.

Evidence & guidelines

Combined corticosteroid-aminoglycoside eye preparations are well established for inflammatory ocular conditions with a bacterial component, with safe use contingent on excluding viral keratitis and limiting duration.

Reference: RCOphth; Drug verified in RxNorm (NLM); confirm dosing against the manufacturer SPC (eMC). Verify against your local formulary and current prescribing references before prescribing. The structured dose values shown have been reviewed by a clinician. Monograph status: clinician-reviewed (2026-07-04).

Related

Curated clinical cross-links plus same-class fallbacks.

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