Fluorometholone + Gentamicin

Uses

Inflammation associated with infections in the anterior segment of the eye due to bacteria susceptible to Gentamicin it is also used for postoperative infection.

Fluorometholone + Gentamicin is also used to associated treatment for these conditions: Anterior chamber inflammation, Conjunctivitis allergic, Corneal Inflammation, Inflammation, Ocular Inflammation, Ocular bacterial infectionsBacterial Conjunctivitis, Bacterial Infections, Bacterial Peritonitis, Bacterial dacryocystitis, Blepharoconjunctivitis, Central Nervous System Infections, Conjunctivitis allergic, Corneal infection, Dermatitis infected, Ecthyma, Eczematous dermatitis infected, Folliculitis, Furunculosis, Gram-negative enteric bacilli neonatal sepsis, Impetigo contagious, Inflammation, Keratitis bacterial, Keratoconjunctivitis, Meibomianitis, Meningitis, Bacterial, Ocular Inflammation, Pustular Psoriasis (PP), Pustular acne, Pyoderma Gangrenosum, Seborrheic Dermatitis, Septicemia gram-negative, Skin Infections, Skin Infections, Bacterial, Skin and Subcutaneous Tissue Bacterial Infections, Sycosis barbae, Bacterial blepharitis, Bacterial corneal ulcers, Bacterial dermatoses, Complicated Bacterial Urinary Tract Infections, Complicated Respiratory tract infection bacterial, Corticosteroid-responsive dermatoses, Ocular bacterial infections, Severe Endocarditis enterococcal, Severe Infection Pseudomonas aeruginosa, Severe Staphylococcal infection

How Fluorometholone + Gentamicin works

There is no generally accepted explanation for the mechanism of action of ocular corticosteroids. However, corticosteroids are thought to act by the induction of phospholipase A2 inhibitory proteins, collectively called lipocortins. It is postulated that these proteins control the biosynthesis of potent mediators of inflammation such as prostaglandins and leukotrienes by inhibiting the release of their common precursor, arachidonic acid. Arachidonic acid is released from membrane phospholipids by phospholipase A2. Their primary target is the cytosolic glucocorticoid receptor. After binding the receptor the newly formed receptor-ligand complex translocates itself into the cell nucleus, where it binds to many glucocorticoid response elements (GRE) in the promoter region of the target genes. The DNA bound receptor then interacts with basic transcription factors, causing the increase in expression of specific target genes.

There are 3 key phases of aminoglycoside entry into cells. The first “ionic binding phase” occurs when polycationic aminoglycosides bind electrostatically to negatively charged components of bacterial cell membranes including with lipopolysaccharides and phospholipids within the outer membrane of Gram-negative bacteria and to teichoic acids and phospholipids within the cell membrane of Gram-positive bacteria. This binding results in displacement of divalent cations and increased membrane permeability, allowing for aminoglycoside entry. The second “energy-dependent phase I” of aminoglycoside entry into the cytoplasm relies on the proton-motive force and allows a limited amount of aminoglycoside access to its primary intracellular target - the bacterial 30S ribosome. This ultimately results in the mistranslation of proteins and disruption of the cytoplasmic membrane.[A233320] Finally, in the “energy-dependent phase II” stage, concentration-dependent bacterial killing is observed. Aminoglycoside rapidly accumulates in the cell due to the damaged cytoplasmic membrane, and protein mistranslation and synthesis inhibition is amplified. The necessity of oxygen-dependent active transport explains why aminoglycosides are ineffective against anaerobic bacteria. Hence, aminoglycosides have both immediate bactericidal effects through membrane disruption and delayed bactericidal effects through impaired protein synthesis; observed experimental data and mathematical modeling support this two-mechanism model. Inhibition of protein synthesis is a key component of aminoglycoside efficacy. Structural and cell biological studies suggest that aminoglycosides bind to the 16S rRNA in helix 44 (h44), near the A site of the 30S ribosomal subunit, altering interactions between h44 and h45. This binding also displaces two important residues, A1492 and A1493, from h44, mimicking normal conformational changes that occur with successful codon-anticodon pairing in the A site.[A232324, A232329] Overall, aminoglycoside binding has several negative effects including inhibition of translation, initiation, elongation, and ribosome recycling. Recent evidence suggests that the latter effect is due to a cryptic second binding site situated in h69 of the 23S rRNA of the 50S ribosomal subunit.[A232329, A232339] Also, by stabilizing a conformation that mimics correct codon-anticodon pairing, aminoglycosides promote error-prone translation.[A232344] Mistranslated proteins can incorporate into the cell membrane, inducing the damage discussed above.

Dosage

Fluorometholone + Gentamicin dosage

Sterile Ophthalmic Suspension:

• Bacterial infection: The dosage depends on the severity of the disease. The application of 1 drop 5 times daily into the conjunctival sac of the affected eye is recommended. In severe cases the dosage can be increased up to 1 drop per hour for 1 to 2 days.
• Ocular postoperative infection: 1 drop 4 times daily into the conjunctival sac for 1 week. Then a reduced application frequency is recommended for the remaining part of the treatment.

Sterile Eye Ointment:

• Bacterial infection: Apply 3-4 times daily into the affected eye.
• Ocular postoperative infection: To support the therapy with Ophthalmic Suspension during the night apply ointment before retiring.

Side Effects

A transient burning sensation may occur after instillation. Rare: Hypersensitivity reactions including eczema of the eyelid and puncture keratitis. Prolonged use of topical steroids may delay wound healing, increase of IOP, develop cataract and cause thinning of cornea & sclera.

Toxicity

Side effects may include acute anterior uveitis and perforation of the globe. Keratitis, conjunctivitis, corneal ulcers, mydriasis, conjunctival hyperemia, loss of accommodation and ptosis have occasionally been reported following local use of corticosteroids. LD₅₀ = 234 mg/kg (rats)

As with other aminoglycosides, nephrotoxicity and ototoxicity are associated with gentamicin. Signs of nephrotoxicity include an increase in plasma creatinine and urea, while signs of ototoxicity include issues with balance, nausea, tinnitus, and hearing loss. It is important to note that aminoglycoside-induced nephrotoxicity is typically reversible, while ototoxicity is more likely to be permanent. The risk of both toxicities increases with long-term gentamicin therapy. Gentamicin is considered to be more vestibulotoxic than cochleotoxic compared to other aminoglycosides. Unfortunately, gentamicin-related ototoxicity does not correlate with cumulative dosing, peak and trough levels, or dosing schedule. The unpredictability of ototoxicity supports close monitoring of the patient throughout treatment. In cases of toxicity or overdose, the medication should be discontinued immediately; hemodialysis may be initiated to lower gentamicin serum concentrations.

Precaution

Steroids can mask, activate or aggravate ocular infections.

Long term treatment with steroid may enhance thinning of cornea and sclera and rarely perforation of the cornea has been reported.

In case no improvement is observed after 7-8 days of treatment, other therapeutical means should be considered.

Patients experiencing blurred vision after application of the product, particularly the ointment, should refrain from driving vehicles or operating machinery.

Contact lenses should be removed before each application.

Interaction

Specific drug interaction studies have not been conducted with Fluorometholone ophthalmic suspension.

None has been reported so far with topical and Eye/Ear drops.

Half Life

One study assessing the pharmacokinetics of gentamicin in children and adults reported a mean half-life of 75 minutes after intravenous administration. The mean half-life associated with intramuscular administration was about 29 minutes longer. Fever and anemia may result in a shorter half-life although dose adjustments are not usually necessary. Severe burns are also associated with a shorter half-life and may result in lower gentamicin serum concentrations.

Clearance

The renal clearance of gentamicin is comparable to individual creatinine clearance.

Elimination Route

Gentamicin is excreted primarily by the kidneys. In patients with normal renal function, 70% or more of an initial gentamicin dose can be recovered in the urine within 24 hours. Excretion of gentamicin is significantly reduced in patients with renal impairment.

Pregnancy & Breastfeeding use

No controlled studies in humans are available. Administration during pregnancy and lactation is therefore not recommended, except for compelling reasons.

Contraindication

Hypersensitivity to any of the components. Injuries and ulceration of the cornea. Viral infections (e.g. Herpes simplex, Vaccinia) or mycosis. Eye tuberculosis. Glaucoma.

Storage Condition

Store in a cool, dry place and protected from light. Keep out of the reach of children. Discard the container 4 weeks after opening.

To avoid contamination, do not touch the tip of the container to the eye, eyelid or any surface.

Innovators Monograph

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