Bactericidal, anti-inflammatory, anti-allergic and decongestant vasoconstrictor.
Pharmacokinetics and pharmacodynamics in humans
The anti-inflammatory and antiallergic effect of dexamethasone, present in Tedexa-N, is effective when administered topically, thanks to its high solubility in aqueous medium and easy combination with tear fluid or nasal mucus. The onset of the effect is immediate and it prolongs its local activity in a variable way according to the amount of tears and secretion of the nasal mucosa, therefore its administration varies according to these factors.
Corticosteroids suppress the inflammatory response to a variety of agents and are likely to delay or lengthen healing. Because corticosteroids can inhibit the body’s defense mechanism against infection, concomitant use of an antimicrobial drug is recommended when this inhibition is considered clinically significant. Dexamethasone is a powerful steroid.
The antibiotic component of the combination (tobramycin) is included to provide action against susceptible organisms. In vitro studies have shown that the antibiotic tobramycin is active against susceptible strains of the following micro-organisms: Staphylococci, including S. aures and S. epidermis (coagulose-positive and coagulose-negative) and penicillin-resistant strains. Streptococci including some of the group a beta-hemolytic and some non-hemolytic species and some strains of Streptococcus pneumoniae pseudomona aeuroginosa, Escherichia coli, Klebsiella peumoniae, Enterobacter aerógenes, Proteus mirabilis, Morganella morganii, most of the strains of Proteus vulgaris H. Aegyptius, Moraxella lacunata and Anicetobacter calcoaceticus and some species of neisseria.
Nafazolin is an imidazoline sympathomimetic drug with vasoconstrictor action on the vascular system of the conjunctiva. This effect is presumed to be due to direct stimulation of the drug on alpha-adrenergic receptors in the arterioles of the conjunctiva, leading to decreased conjunctival congestion.
Each ml of suspension contains:
Tobramycin 3 mg
Dexamethasone 1 mg
Nafazolin HCl 0.25 mg
Excipients and purified water C.S.P. 1 ml
Posology and administration
Administration route: Ophthalmic.
Suspension: Shake well before use. One or two drops instilled into the conjunctival sac every four to six hours. During the initial 24 to 48 hours, the dosage can be increased to one or two drops every two (2) hours. The frequency should be gradually decreased as improvement in clinical signs is obtained. Take caution not to discontinue therapy prematurely.
Keep at a temperature between 15 °C and 25 °C. Protect from freezing.
Dropper bottle with 5 ml of suspension.
Tedexa-N is indicated in inflammatory eye conditions that respond to steroids, and in which there is also a risk of a superficial bacterial eye infection; or the existence of the same and congestion of the tissues.
Ocular steroids are indicated in inflammations of the palpebral and bulbar conjunctiva, cornea and anterior segment of the eye, to obtain a decrease in edema or inflammation. It is also indicated in chronic anterior uveitis and corneal wounds due to chemical, thermal, or radioactive burns or foreign body penetration. The use of a combination of drugs with an anti-infective component is indicated when the risk of superficial ocular infection is high or when there is a potentially dangerous number of bacteria at the ocular level.
Tedexa-N is contraindicated in narrow angle glaucoma, herpes simplex epithelial keratitis (dendritic keratitis), vaccinia, chickenpox, and many other viral diseases of the cornea and conjunctiva. Mycobacterial eye infection, fungal infection of the eye structures. Hypersensitivity to any component of the product. The use of Tedexa-N is always contraindicated after the uncomplicated removal of a foreign body.
Hypersensitivity to topically applied aminoglycosides may occur in some patients. If a hypersensitivity reaction occurs, use should be discontinued.
Prolonged use of steroids can cause glaucoma, with damage to the optic nerve, defects in visual acuity and visual field, and formation of posterior subcapsular cataract. Intraocular pressure should be routinely recorded, even if this is difficult in children and in uncooperative patients. Prolonged use can suppress the patient’s defense response and thus increase the risk of secondary eye infections. In those diseases that cause a thinning of the cornea or sclera, perforations have been reported with the use of topical steroids. In acute purulent infections of the eyeball, steroids can mask the infection and thus promote it.
Corticosteroid application can activate, exacerbate, or mask eye infections from viruses, bacteria, or fungi.
Patients under treatment with MAO inhibitors may experience severe hypertensive crisis if they receive a sympathomimetic agent. The use of Nafazolin in children, especially young children, can cause depression of the CNS to cause coma and a marked reduction in body temperature.
Precautions or recommendations for use during pregnancy and lactation
It should be administered with caution to pregnant women, since its chronic use can cause hypoadrenalism in the product.
Care should be taken when administering these drugs to lactating women.
Safety and effectiveness in children have not been established.
Adverse reactions have occurred with the combination of steroids and anti-infectives that can be attributed to the steroid component, the anti-infective component, or a combination of both. The most frequent adverse reactions against topical ocular administration of tobramycin are: pruritus, eyelid edema and conjunctival erythema. Reactions due to the steroid component are: elevation of intraocular pressure (IOP) with possible development of glaucoma, and infrequently optic nerve damage, formation of posterior subcapsular cataract and delayed healing.
Other reported adverse reactions are:
Eyepieces: mydriasis, malaise, blurred vision, punctate keratitis, tearing. Systemic: dizziness, headaches, nausea, sweating, nervousness, drowsiness, weakness, hypertension, cardiac abnormalities, hyperglycemia.