dexamethasone intraocular

Action and Spectrum

Actions and Spectrum: 

dexamethasone is a corticosteroid medication that has anti-inflammatory and immunosuppressive properties. When administered intraocularly (into the eye), it can help reduce inflammation and swelling. 

dexamethasone intraocular suspension is approved for treating inflammatory conditions of the eye, including postoperative inflammation, noninfectious uveitis, and diabetic macular edema. It binds to glucocorticoid receptors in the eye cells, inhibiting the production and release of inflammatory cytokines, prostaglandins, and leukotrienes. This reduces inflammation, swelling, and pain in the eye. 

The spectrum of action of dexamethasone intraocular suspension is mainly limited to the eye, although some systemic effects may occur, especially with prolonged use. Some possible side effects of dexamethasone intraocular suspension include increased intraocular pressure, cataract formation, infection, and retinal detachment. It is essential to use this medication only as directed by a healthcare professional and report any adverse effects promptly. 

Drug Interaction

Adverse Reaction

Frequency defined 

>10% 

Corneal edema (5-15%) 

Increased intraocular pressure (5-15%) 

Iritis (5-15%) 

1-10% 

Dry eye (1-5%) 

Corneal endothelial cell loss (1-5%) 

Vitreous floaters (1-5%) 

Blurred vision (1-5%) 

Blepharitis (1-5%) 

Posterior capsule opacification (1-5%) 

Eye pain (1-5%) 

Cystoid macular edema (1-5%) 

Vitreous detachment (1-5%) 

Foreign body sensation (1-5%) 

Photophobia (1-5%) 

Reduced visual acuity (1-5%) 

Ocular inflammation (1-5%) 

Black Box Warning

Black Box Warning: 

The black box warning for dexamethasone intravitreal implant is a specific formulation of dexamethasone administered as an implant directly into the eye to treat macular edema succeeding retinal vein occlusion or following cataract surgery. 

The black box warning highlights the potential risk of endophthalmitis, a severe infection inside the eye associated with a dexamethasone intravitreal implant. Endophthalmitis is an infrequent but potentially devastating complication that can cause permanent vision loss. 

The warning also notes that the implant should not be used in patients with active/suspected ocular or periocular infections and that patients should be monitored following administration of the implant for any signs of infection or other adverse events. A qualified healthcare professional with experience in intravitreal injections should only administer the implant. 

It is vital to note that the black box warning pertains specifically to the intravitreal implant formulation of dexamethasone and not to the intraocular suspension formulation, administered differently and for different conditions. However, all formulations of dexamethasone carry a risk of potential adverse effects. 

Contraindication / Caution

Contraindication/Caution: 

Contraindication 

dexamethasone intraocular suspension is contraindicated in patients with known hypersensitivity to dexamethasone or its components. It should generally not be used in patients with active/suspected ocular or periocular infections, including viral, bacterial, or fungal, as it may exacerbate these conditions. 

Other contraindications for dexamethasone intraocular suspension include: 

• Epithelial herpes simplex keratitis, varicella, vaccinia, and many other viral diseases of the cornea, conjunctiva 
• Mycobacterial infections of the eye 
• Fungal diseases of ocular structures 
• Amoebic infections of the eye 
• Acute purulent untreated infections of the eye 

Additionally, caution should be exercised when using dexamethasone intraocular suspension in patients with glaucoma or a history of glaucoma, as it may increase intraocular pressure. The suspension should also be used cautiously in patients with a history of cataract surgery, as it may increase the risk of cataract formation. 

It is key to discuss any medical conditions, medications, or allergies with a healthcare professional before using dexamethasone intraocular suspension, as it may interact with other medications or exacerbate certain conditions. 

Caution 

dexamethasone intraocular suspension should be used with caution in certain patients and situations. These include: 

• Patients with a prior history of herpes simplex virus (HSV) infection of the eye: dexamethasone can reactivate HSV infection, leading to severe complications. Therefore, patients with a history of HSV infection of the eye should be closely monitored when using dexamethasone intraocular suspension, and antiviral therapy may be necessary. 
• Patients with a history of glaucoma or high intraocular pressure: dexamethasone can increase intraocular pressure, which can exacerbate glaucoma or lead to the development of glaucoma in patients with a prior history of elevated intraocular pressure. Therefore, these patients should be closely monitored while using dexamethasone intraocular suspension. 
• Pediatric patients: The safety and effectiveness of dexamethasone intraocular suspension have not been established in pediatric patients. The suspension should be used cautiously in this population, and the benefits and risks should be carefully weighed before use. 
• Prolonged use: dexamethasone intraocular suspension can increase the risk of infection, cataract formation, and intraocular pressure. Therefore, it should be used for the shortest duration possible to achieve the desired therapeutic effect. 
• Pregnancy and breastfeeding: The safety of dexamethasone intraocular suspension in pregnant or breastfeeding women has not been established.  

It is key to discuss any medical conditions, medications, or allergies with a healthcare professional before using dexamethasone intraocular suspension, as it may interact with other medications or exacerbate certain conditions. 

Pregnancy / Lactation

Pregnancy consideration:  

AU TGA pregnancy category: B3
US FDA pregnancy category: C 

Lactation:   

Excreted into human milk: Yes 

Pregnancy category: 

• Category A: well-controlled and Satisfactory studies show no risk to the fetus in the first or later trimester. 
• Category B: there was no evidence of risk to the fetus in animal studies, and there were not enough studies on pregnant women. 
• Category C: there was evidence of risk of adverse effects in animal reproduction studies, and no adequate evidence in human studies must take care of potential risks in pregnant women.    
• Category D: adequate data with sufficient evidence of human fetal risk from various platforms, but despite the potential risk, and used only in emergency cases for potential benefits.    
• Category X: Drugs listed in this category outweigh the risks over benefits. Hence these categories of drugs need to be avoided by pregnant women.    
• Category N: There is no data available for the drug under this category 

Pharmacology

Pharmacology: 

dexamethasone intraocular suspension is a potent synthetic glucocorticoid steroid medication that acts as an anti-inflammatory and immunosuppressive agent. It binds to specific glucocorticoid receptors in target cells, leading to various gene expression and protein synthesis effects. 

The exact mechanism of action of dexamethasone intraocular suspension has yet to be fully understood. Still, it is thought to inhibit the production of inflammatory cytokines, chemokines, and other mediators of inflammation, such as prostaglandins and leukotrienes. Reducing inflammation can help alleviate symptoms such as swelling, redness, pain, and discomfort. 

dexamethasone intraocular suspension has a half-life of approximately 3 hours, and it is rapidly metabolized and eliminated from the body. The drug is not known to accumulate in the eye or other tissues, and systemic absorption is minimal when used as directed. 

It is important to note that dexamethasone intraocular suspension can have various side effects, including increased intraocular pressure, cataract formation, and the potential for infection. It is also contraindicated in certain patients and situations and should only be used under the supervision of a healthcare professional with experience administering ocular medications. 

Pharmacodynamics: 

Mechanism of action: The action of corticosteroids involves the suppression of inflammation by inhibiting multiple inflammatory cytokines, leading to a decrease in edema, capillary leakage, fibrin deposition, and migration of inflammatory cells. 

Pharmacokinetics: 

Absorption 

dexamethasone intraocular suspension is rapidly absorbed into the ocular tissues after installation. Some drugs may also be absorbed into the systemic circulation through the conjunctival and episcleral blood vessels. 

Distribution 

dexamethasone is extensively bound to plasma proteins and distributed throughout the body. It can cross the blood-brain barrier (BBB) and the placenta and also found in breast milk. 

Metabolism 

Various enzymes extensively metabolize dexamethasone in the liver, including cytochrome P450. It undergoes oxidation, reduction, and conjugation to form various metabolites, which are then excreted in the urine. 

Elimination and Excretion 

dexamethasone and its metabolites are primarily excreted in the urine, with a small quantity being excreted in the feces. The half-life of dexamethasone is approximately 3 hours, and it is eliminated from the body. 

Adminstartion

Administration: 

Intraocular administration 

dexamethasone intraocular suspension is administered directly into the eye by a healthcare professional. The specific administration technique may vary depending on the treated condition and the healthcare provider’s preference. 

The most common method of administration involves the following steps: 

• The eye and surrounding area are cleansed with an antiseptic solution. 
• The healthcare provider uses a local anesthetic to numb the eye’s surface. 
• The provider uses a sterile instrument to hold the eyelids open. 
• The provider then applies pressure to the eye with a sterile instrument to create a small opening in the eye’s surface. 
• A sterile dropper is used to instill the dexamethasone intraocular suspension into the eye through the opening. 
• The eye is then monitored for any adverse reactions. 

After administration, the patient may be instructed to use antibiotics and anti-inflammatory eye drops to prevent infection and reduce inflammation. It is essential to follow all healthcare provider’s instructions and promptly report any adverse reactions or concerns. 

It is also important to note that dexamethasone intraocular suspension is a prescription medication and should be used only under the observation of a physician with experience in administering ocular medications. 

Patient Information Leaflet

Patient information leaflet 

Generic Name: dexamethasone intraocular 

Pronounced: [ DEX-a-METH-a-sone ] 

Why do we use dexamethasone intraocular?  

dexamethasone intraocular suspension is a steroid medication that is used to treat various ocular conditions that involve inflammation, including: 

• Postoperative inflammation: dexamethasone intraocular suspension can be used after cataract surgery or other ocular surgeries to reduce inflammation and swelling in the eye. 
• Non-infectious uveitis: dexamethasone intraocular suspension can reduce inflammation in the uvea, the eye’s middle layer. 
• Macular edema: dexamethasone intraocular suspension can be used to treat macular edema, a condition that involves swelling of the macula, the central part of the retina. 
• Allergic conjunctivitis: dexamethasone intraocular suspension can reduce inflammation in the conjunctiva, which is the membrane that covers the white part of the eye, inner surface of the eyelids, in patients with allergic conjunctivitis. 
• Episcleritis and scleritis: dexamethasone intraocular suspension can reduce inflammation in the episclera or sclera, the outer layers of the eye. 

It is important to note that dexamethasone intraocular suspension is a prescription medication and should only be used under the observation of a healthcare professional with experience administering ocular medications.