Presentation Dexagen T Suspension: Each ml sterile ophthalmic suspension contains Dexamethasone USP 1 mg &Tobramycin USP 3 mg. Preservative: Benzalkonium Chloride 0.01%. Dexagen T Ointment: Each gm sterile eye ointment contains Dexamethasone USP 1 mg & Tobramycin USP 3 mg.