Lisdexamfetamine

Abstract

Bilateral acute angle closure: case report A 14-year-old boy experienced bilateral acute angle closure during treatment with lisdexamfetamine for attentiondeficit/hyperactivity disorder [ADHD; route and duration of treatment to reaction onset not stated]. The boy, whose medical history was notable for ADHD, presented to hospital with photophobia, bilateral eye pain, headache, nausea and vomiting. He had been out of school for the previous 6 months due to the COVID-19 pandemic; during this time, he had not been taking lisdexamfetamine [Vyvanse; lisdexamfetamine dimesylate], which he had previously been receiving at a dose of 30mg per day for 2 years. On his first day of school (through virtual learning), he received lisdexamfetamine 30mg. He subsequently developed blurry (distance) vision, nausea, vomiting and headache. On examination, his uncorrected distance vision was 20/400 in both eyes, and the near visual acuity was J1+ in both eyes. His pupils were sluggishly reactive to light, with no relative afferent pupillary defect. The intraocular pressure (IOP) in his right and left eyes was 41 and 43mm Hg, respectively. On bilateral gonioscopy, a clear cornea was visualised, with a shallow anterior chamber and appositionally closed angles. His central anterior chamber was about two corneal thicknesses deep. Examination of the fundus was unremarkable, with a bilateral cup-to-disc ratio of 0.3. The boy was treated with acetazolamide, brimonidine, dorzolamide and timolol, after which his pain subsided and his IOP decreased to the 20s. His pupils then became briskly reactive. He was advised to discontinue lisdexamfetamine. After approximately 12 hours, a laser peripheral iridotomy (LPI) was performed in his right eye, with a rapid rush of fluid through the patent iridotomy, accompanied by immediate deepening of the anterior chamber. After 1 week, LPI was performed in his left eye. One week later, he resumed lisdexamfetamine at the same dose. Two weeks following the second LPI, his uncorrected distance visual acuity returned to 20/20 in both eyes, while his IOP was 15mm Hg bilaterally (without ongoing IOP lowering agents). Gonioscopy revealed D40r angles in all four quadrants. No other abnormalities were detected. He was encouraged to continue lisdexamfetamine, as his chamber remained deep, and his IOP normalised. His cup-to-disc ratio remained unchanged at 0.3. Ocular coherence tomography (OCT) performed 1 week following the second LPI revealed normal retinal nerve fibre layer thickness for age. Glaucomatous optic atrophy was not evidenced. Axial length, lens thickness, anterior chamber depth and average corneal power was 24.31mm, 3.4mm, 3.80mm and 41.25D in the right eye, respectively, and 24.37mm, 3.38mm, 3.79mm and 40.96 D in the left eye, respectively. Pentacam was compatible with biometry results; anterior segment OCT revealed open anterior chamber angle with flat iris configuration.