Is a headache or brow ache normal after SLT laser treatment?

What's normal

The Glaucoma Research Foundation describes SLT as typically painless or causing only minor discomfort, and says post-operative inflammation is common but generally mild with the vast majority of complications mild and self-limiting. A dull ache over the brow on the treated side, easing over the first hours to a day, generally falls in that minor discomfort category.

Keeping the eye open under a contact lens, the bright laser light that BrightFocus Foundation and the Glaucoma Research Foundation describe, and squinting from light sensitivity all contribute. The published sources do not give a specific expected duration for brow ache after SLT, so use the general take-it-easy day or two as your frame and report anything outside it.

Mild brow ache usually eases within hours. Headache plus eye pain, nausea, or halos is an urgent call at any point.

When it stops being normal

A headache is one of the specific warning symptoms the American Academy of Ophthalmology lists for a dangerous rise in eye pressure. Its emergency list includes sudden blurry vision, severe eye pain, headache, feeling sick to your stomach or vomiting, and rainbow-colored rings or halos around lights. The Academy calls that combination a true eye emergency and says to call your ophthalmologist right away.

StatPearls notes that a rise in intraocular pressure is the most common complication of laser trabeculoplasty, which is why headache paired with eye symptoms after SLT is taken seriously rather than treated as ordinary. Do not wait it out with a pain reliever if eye pain, nausea, or vision changes are part of the picture.