Pregabalin and gabapentin for post-photorefractive keratectomy pain: a randomized controlled trial

PURPOSE. To evaluate the efficacy of pregabalin and gabapentin for reducing post-photorefractive keratectomy (PRK) pain. METHODS. In this randomized clinical trial, 150 subjects undergoing PRK were allocated into 3 groups. In addition to the routine regimen, pregabalin 75 mg, gabapentin 300 mg, and placebo were administered 3 times daily for 3 days, in groups 1, 2, and 3, respectively. Subjects could take acetaminophen-codeine 300/10 mg tablets every 4 hours as needed. Patients completed a pain assessment survey (visual analogue scale ranging from 0 = no pain to 10 = most severe pain) 7 times in the first 3 days following PRK and also recorded the number of consumed acetaminophen-codeine tablets. RESULTS. Age, sex, refractive error, ablation depth, and mitomycin-C (MMC) application were similar in the 3 study groups (all p values>0.05). Overall pain scores in the placebo group were 0.9 and 1 unit higher than the pregabalin (p=0.029) and gabapentin (p=0.023) groups, respectively. Severe pain (score >7) was more frequent in the placebo group on the morning of the first postoperative day (p=0.043). The difference in the number of consumed acetaminophen-codeine tablets was statistically borderline (p=0.061) and less in the pregabalin (7.9 +/- 5.2) and gabapentin (9.0 +/- 4.1) groups in comparison to the placebo group (10.3 +/- 5.6). CONCLUSIONS. Pregabalin and gabapentin seem to be helpful in alleviating post-pRK pain when combined with other measures. Depending on availability, either compound can be used as an adjuvant for pain control in this setting.