Is an eye ache or soreness normal after SLT laser treatment?

What's normal

The Glaucoma Research Foundation says SLT is typically painless or results only in minor discomfort, and that you may feel a slight tingling sensation during the procedure. BrightFocus Foundation uses the same description and mentions occasional pinprick sensations during treatment. The American Academy of Ophthalmology notes you may feel a stinging sensation as the laser is used.

Afterward, a dull ache or gritty soreness usually reflects the mild inflammation that the Glaucoma Research Foundation says is common but generally mild, plus the contact lens that sat on the surface of the eye during treatment. Anti-inflammatory drops are typically prescribed for a couple of days and are aimed at exactly this. The Glaucoma Research Foundation's advice to take it easy for a day or two before returning to your routine fits this pattern.

Usually mild and improving within the first day or two, alongside the prescribed anti-inflammatory drops.

When it stops being normal

Pain that is severe, that keeps increasing, or that is not settling over the first day is not the expected course. The American Academy of Ophthalmology lists eye pain among the possible complications of laser trabeculoplasty and describes severe eye pain with sudden blurry vision, headache, nausea, vomiting, or halos around lights as a true eye emergency requiring an immediate call.

StatPearls notes that a rise in intraocular pressure is the most common complication of laser trabeculoplasty, and also lists low-grade iritis and corneal edema. Any of those can present as an aching, painful eye. Do not try to sort out which one you have on your own. Report worsening pain to your ophthalmologist.