Tobramycin

These indications are based on manufacturer information for both originator and generic products. For product specific registered indications, please refer to product specific manufacturer information

Registered South African indications:

• External bacterial infections of the eye and its adnexa caused by susceptible organisms

Registered South African contraindications

• Hypersensitivity to the active ingredient or any of its excipients

South African recommendations

• Breastfeeding

Sensitivity to topically applied aminoglycosides

• Some patients may show sensitivity, discontinue tobramycin if this occurs

Cross-hypersensitivity concerns

• Patients sensitive to topical ocular tobramycin might also react to other aminoglycosides

Potential systemic aminoglycoside reactions

• Systemic aminoglycoside therapy can lead to neurotoxicity, ototoxicity, and nephrotoxicity. Exercise caution when combined with ophthalmic tobramycin

Neuromuscular disorder concerns

• Tobramycin might exacerbate muscle weakness in individuals with conditions like myasthenia gravis or Parkinson’s disease

Local ocular reactions and serum monitoring

• There's a possibility of local ocular toxicity or hypersensitivity. If used with systemic aminoglycosides, ensure serum level monitoring

Risks associated with prolonged use

• Extended use can result in skin sensitivity or non-susceptible organism growth. Address any arising superinfections

Effects on corneal healing

• Ophthalmic ointments may decelerate corneal healing

Issues with benzalkonium chloride use

• Prolonged use, especially with benzalkonium chloride preserved products like tobramycin, can affect corneal health. Regular ophthalmological examination is required

Contact lens considerations during infection

• Wearing contact lenses is not recommended while treating an ocular infection

Interactions of benzalkonium chloride with contact lenses

• Tobramycin eye drops, due to benzalkonium chloride, may irritate the eyes and alter the colour of soft contact lenses
• Remove lenses before applying tobramycin eye drops and wait at least 15 minutes after application before reinserting

Forms avail. in SA and covered in this monograph: opd, eyo

Infections caused by: Staph. aureus, Enterobacteriaceae (most of the family); Pseud. aeruginosa; Most Staphylococci; Most gram-negative bacteria; Pseudomonas; Klebsiella and Enterobacter (aerobacter); E. Coli and indole-positive and -negative; Proteus

Specific doses based on individual indications

Please note that the dosages below should be used in combination with regional guidelines, taking into account local antibiotic sensitivities

South African registered indications and dosages

External bacterial infections of the eye and its adnexa caused by susceptible organisms
- Mild to moderate infections

• Ophthalmic (opd): Instil 1-2 drops into the conjunctival sac of the affected eye(s), 4hrly; Treatment duration: 7 days
• Ophthalmic (eyo): Apply a 10mm (half an inch) ribbon into the affected eye(s), 2-3 times a day

- Severe infections

• Ophthalmic (opd): Instil 2 drops into the conjunctival sac of the affected eye(s), 1hrly until improvement; Follow with dose reduction prior to discontinuation
• Ophthalmic (eyo): Apply a 10mm (half an inch) ribbon into the affected eye(s), 3-4hrly until improvement; Follow with dose reduction prior to discontinuation

---

Appropriate monitoring of bacterial response to topical antibiotic therapy should accompany the use of tobramycin

Paed. forms avail. in SA and covered in this monograph: opd, eyo

Infections caused by: Staph. aureus, Enterobacteriaceae (most of the family); Pseud. aeruginosa. Most Staphylococci; Most gram-negative bacteria; Pseudomonas; Klebsiella and Enterobacter (aerobacter); E. Coli and indole-positive and -negative; Proteus

Specific doses based on individual indications

Please note that the dosages below should be used in combination with regional guidelines, taking into account local antibiotic sensitivities

South African Standard Treatment Guidelines indications and dosages

Complicated bacterial eye infection - severe

• Ophthalmic (opd): Instil 1 drop into the affected eye(s), 4-6hrly during the day 
• Ophthalmic (eyo): Apply into the affected eye(s) at night
  (STG, Paed. 2023)

---

No information available in South African manufacturer's professional information on the use of tobramycin ophthalmic in children

Pregnancy

• Safe; no evidence of risk in studies 
• Animal studies have not revealed any harm or occurrence of adverse events. During pregnancy, the minimum effective dose should be used if treatment is deemed necessary. Systemic absorption following ophthalmic use is expected to be low

Breastfeeding

• Caution
• The minimum effective dose should be used if ophthalmic tobramycin is required in breastfeeding women. A risk to the breastfeeding child cannot be excluded. A decision should be made whether to discontinue breastfeeding or to abstain from treatment taking into consideration the benefit of breastfeeding for the infant and the benefit of therapy for the breastfeeding mother

Renal Impairment

• No dose adjustment recommended

Hepatic Impairment 

• No dose adjustment recommended

Elderly 

• No dose adjustment recommended

Porphyria Information

• Not porphyrinogenic (NP)

Drugs in Sport

• Permitted - No warnings

Skin and Subcutaneous Tissue Disorders

• Eyelid erythema
• Eyelid pruritus

Immune, Blood and Lymphatic System Disorders 

• Hypersensitivity 

Sensory Disorders

• Conjunctival erythema

Systemic aminoglycosides

None routine

Interferes with bacterial protein synthesis by binding to 30S ribosomal subunit resulting in a defective bacterial cell membrane.

Eye drops (per ml) 3mg

• Tobrex (Novartis South Africa) Originator
• Toryn (Actor Pharma)

Eye ointment (per ml) 3mg

• Tobrex (Novartis South Africa) Originator

Also available in the following forms: Nebulising solution and injection

COMBINATION PREPARATIONS

Dexamethasone/ Tobramycin

Eye drops (per 5ml) 1mg/0.3%

• Tobradex (Novartis South Africa) originator

Eye ointment (per 3.5g) 1mg/0.3%

• Tobradex (Novartis South Africa) originator