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Drug Details

Maxitrol ointment

• Drug Class Description
  Pharmacotherapeutic group: ophthalmologicals; anti-infectives ATC code: S01CA01 Mechanism of Action MAXITROL eye ointment has a dual effect: suppression of inflammation symptoms by the corticosteroidal component dexamethasone, and an anti-infective effect due to the presence of two antibiotics, polymyxin B and neomycin. Dexamethasone is a synthetic glucorticoid with potent anti-inflammatory activity. Polymyxin B is a cyclic lipopeptide that penetrates the cell wall of gram-negative bacilli to destabilize the cytoplasmic membrane. It is generally less active against gram-positive bacteria. Neomycin is an aminoglycoside antibiotic that primarily exerts its effect on bacterial cells by inhibiting polypeptide assembly and synthesis on the ribosome. Mechanism of Resistance Resistance of bacteria to polymyxin B is of chromosomal origin and is uncommon. A modification of the phospholipids of the cytoplasmic membrane appears to play a role. Resistance to neomycin occurs by several different mechanisms including (1) alterations of the ribosomal subunit within the bacterial cell; (2) interference with the transport of neomycin into the cell, and (3) inactivation by an array of adenylating, phosphorylating, and acetylating enzymes. Genetic information for production of inactivating enzymes may be carried on the bacterial chromosome or on plasmids. Breakpoints Each gram of MAXITROL eye ointment contains 6000 IU polymyxin B sulphate and 3500 IU neomycin sulphate. The breakpoints and the in vitro spectrum as mentioned below are based on the dual activity of either polymyxin B or neomycin. The breakpoints listed here are based upon acquired resistance for specific species found in ocular infections and the ratio in International Units of polymyxin B to neomycin in MAXITROL eye ointment: Resistance breakpoints: >5:2.5 to >40:20 depending upon the bacterial species Susceptibility The information listed below provides guidance on the approximate probabilities on the susceptibility of microorganisms to polymyxin B or neomycin in MAXITROL eye ointment. The presentation below lists bacterial species recovered from external ocular infections of the eye. The prevalence of acquired resistance may vary geographically and with time for selected species and local information on resistance is desirable, particularly when treating severe infections. As necessary, expert advice should be sought when the local prevalence of resistance is such that the utility of the combination of polymyxin B or neomycin as in MAXITROL eye ointment in at least some types of infections is questionable. COMMONLY SUSCEPTIBLE SPECIES Aerobic Gram-positive microorganisms Bacillus cereus Bacillus megaterium Bacillus pumilus Bacillus simplex Corynebacterium accolens Corynebacterium bovis Corynebacterium macginleyi Corynebacterium propinquum Corynebacterium pseudodiphtheriticum Staphylococcus aureus (methicillin susceptible - MSSA) Staphylococcus capitis Staphylococcus epidermidis (methicillin susceptible - MSSE) Staphylococcus pasteuri Staphylococcus warneri Streptococcus mutans Aerobic Gram-negative microorganisms Haemophilus influenzae Klebsiella pneumoniae Moraxella catarrhalis Moraxella lacunata Pseudomonas aeruginosa Serratia species SPECIES FOR WHICH ACQUIRED RESISTANCE MIGHT BE A PROBLEM Staphylococcus epidermidis (methicillin resistant - MRSE) Staphylococcus hominis Staphylococcus lugdunensis INHERENTLY RESISTANT ORGANISMS Aerobic Gram-positive microorganisms Enterococci faecalis Staphylococcus aureus (methicillin resistant - MRSA) Streptococcus mitis Streptococcus pneumoniae Aerobic Gram-negative microorganisms Serratia species Anaerobic Bacteria Propionibacterium acnes Dexamethasone is a moderately powerful corticosteroid having good penetration in ocular tissue. Cortico-steroids have an anti-inflammatory as well as a vasoconstrictive effect. They suppress the inflammatory response and symptoms in various disorders without basically curing these disorders.
• Generic Name
  dexamethasone, polymyxin b sulphate, neomycin sulphate
• Presentation
  Eye ointment White to very pale yellow homogeneous translucent ointment
• Description
  1 gram ointment contains 1 mg dexamethasone, 6000 IU polymyxin B sulphate, and 3500 IU neomycin sulphate (as base)
• Indications
  

  MAXITROL eye ointment is indicated for the short-term treatment of steroid responsive conditions of the eye when prophylactic antibiotic treatment is also required, after excluding the presence of fungal and viral disease.

• Adult Dosage
  

  Children and Adults (including the Elderly)

  Apply a small amount into the conjunctival sac(s) up to three to four times daily or, may be used adjunctively with drops at bedtime.

• Child Dosage
  

  Children and Adults (including the Elderly)

  Apply a small amount into the conjunctival sac(s) up to three to four times daily or, may be used adjunctively with drops at bedtime.

• Elderly Dosage
  

  Children and Adults (including the Elderly)

  Apply a small amount into the conjunctival sac(s) up to three to four times daily or, may be used adjunctively with drops at bedtime.

• Contra Indications
  

  • Hypersensitivity to the active substances or to any component of the preparation.

  • Epithelial herpes simplex keratitis.

  • Vaccinia, varicella, or other viral infection of cornea and conjunctiva (except herpes zoster keratitis).

  • Fungal diseases of ocular structures.

  • Mycobacterial ocular infections.

• Special Precautions
  

  • For topical ophthalmic use only. Not for injection or ingestion.

  • As with all antibacterial preparation prolonged use may lead to overgrowth of non-susceptible bacterial strains or fungi. If superinfection occurs, appropriate therapy should be initiated.

  • Sensitivity to topically applied aminoglycosides may occur in some patients. Cross-sensitivity to other aminoglycosides may also occur. If signs of serious reactions or hypersensitivity occur, discontinue use of MAXITROL eye ointment.

  • Patients using ophthalmic preparations containing neomycin sulphate should be advised to consult a physician if ocular pain, redness, swelling, or irritation worsens or persists.

  • Serious adverse reactions including neurotoxicity, ototoxicity and nephrotoxicity have occurred in patients receiving systemic neomycin or when applied topically to open wounds or damaged skin. Nephrotoxic and neurotoxic reactions have also occurred with systemic polymyxin B. Although these effects have not been reported following topical ocular use of this product, caution is advised when used concomitantly with systemic aminoglycoside or polymyxin B therapy.

  • Prolonged use of ophthalmic use may result in ocular hypertension and/or glaucoma, with damage to the optic nerve, reduced visual acuity and visual field defects, and posterior subcapsular cataract formation. In patients receiving prolonged ophthalmic corticosteroid therapy, intraocular pressure should be checked routinely and frequently.

  • In those diseases causing thinning of the cornea or sclera, perforations have been known to occur with the use of topical corticosteroids.

  • Corticosteroids may reduce resistance to and aid in the establishment of bacterial, viral, or fungal infections and mask the clinical signs of infection, preventing recognition of ineffectiveness of the antibiotic, or may suppress hypersensitivity reactions to substances in the product. Fungal infection should be suspected in patients with persistent corneal ulceration who have been or are receiving these drugs and corticosteroid therapy should be discontinued if fungal infection occurs.

  • To avoid the risk of enhancement of herpetic corneal disease, frequent slip lamp examination is essential.

  • Contact lens wear is not recommended during treatment of an ocular infection. Therefore patients should be advised not to wear contact lenses during treatment with MAXITROL eye ointment.

• Interactions
  

  No interaction studies have been performed.

  Concomitant and/or sequential use of an aminoglycoside (neomycin) and other systemic, oral, or topical drugs that have neurotoxic, ototoxic, or nephrotoxic effects may result in additive toxicity and should be avoided, whenever possible.

  If more than one ophthalmic medicinal product is being used, the medicines must be administered at least 5 minutes apart.

• Adverse Drug Reactions
  

   

  Tabulated summary of adverse reactions

  The following adverse effects are classified according to the following convention: very common (1/10), common (1/100 to <1/10), uncommon (1/1,000 to <1/100), rare (1/10,000 to <1/1000), very rare (<1/10,000) or not known (cannot be estimated from the available data). Within each frequency grouping, undesirable effects are presented in decreasing order of seriousness. The adverse reactions were obtained from clinical trials and postmarketing spontaneous reports.

   

  System Organ Classification	MedDRA Preferred Term (v.12.0)
  Immune system disorders	Not Known: hypersensitivity (systemic or ocular)
  Nervous system disorders	Not known: headache
  Eye disorders	Uncommon: keratitis, intraocular pressure increased, eye irritation, eye pruritus, ocular discomfort Not known: corneal thinning, photophobia, blurred vision, mydriasis, eye pain, eye swelling, ptosis, foreign body sensation in eyes, increased lacrimation, ocular hyperaemia

   

  Description of selected adverse event

  Due to the steroid component, in diseases causing thinning of the cornea or sclera there is a higher risk for perforation especially after long treatments.

  Topical ophthalmic steroid use may result in increased intraocular pressure with damage to the optic nerve, reduced visual acuity and visual field defects. Also it may lead to posterior subcapsular cataract formation.

  Sensitivity to topically administered aminoglycosides may occur in some patients. Systemic side effects may occur with extensive use.