Oral versus topical diclofenac for pain prevention during panretinal photocoagulation.
OBJECTIVE
To investigate the effect of pretreatment oral and topical diclofenac on pain reduction during panretinal laser photocoagulation (PRP) for proliferative diabetic retinopathy (PDR).


METHODS
Prospective, randomized, double-masked, placebo-controlled clinical trial.


METHODS
A total of 90 patients with PDR requiring PRP for the first time were assigned randomly to 1 of 3 study groups: oral diclofenac (n = 30), topical diclofenac (n = 31), or placebo (n = 29).


METHODS
Study medications were administrated before the first PRP treatment, and pain levels experienced during and 15 minutes after PRP were recorded on a visual analog scale (VAS). Pain levels during a second PRP session, performed on a later date with no pretreatment medications, also were recorded on a VAS.


METHODS
The primary outcome measures were the mean VAS pain scores during the first PRP treatment. Secondary outcome measures were the mean VAS pain scores 15 minutes after the first PRP and during the second PRP, and reported side effects after the first PRP.


RESULTS
Mean VAS pain scores during the first PRP were: oral diclofenac, 25.7+/-19.9; topical diclofenac, 33.8+/-27.9; and placebo, 41.3+/-31.0. The pain score difference between oral diclofenac and placebo was both clinically significant (>or=13) and statistically significant (P = 0.02), whereas differences between oral and topical diclofenac (P = 0.20) and topical diclofenac and placebo (P = 0.33) were not. Multivariate regression analysis for age, gender, and total laser energy demonstrated lower pain levels for both oral diclofenac (P = 0.015) and topical diclofenac (P<0.0001) versus placebo, but no difference between oral and topical diclofenac (P = 0.67). For the first PRP, all 3 groups had lower mean pain scores at 15 minutes after treatment compared with during treatment (P<or=0.0003). Mean pain scores were higher during the second compared with the first PRP for the oral diclofenac (P = 0.02) and placebo (P = 0.05) groups. No significant rate difference for any side effect was found between groups.


CONCLUSIONS
When given in a single dose, oral diclofenac is an effective pretreatment analgesic agent for reducing the pain experienced during PRP for PDR.


BACKGROUND
The author(s) have no proprietary or commercial interest in any materials discussed in this article.
Department of Ophthalmology, University of British Columbia, Vancouver, Canada.
Peter A
PA
Zakrzewski
Heather L
HL
O'Donnell
Wai-Ching
WC
Lam
D000284:Administration, Oral; D000287:Administration, Topical; D000698:Analgesia / Q000379:methods; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000008:administration & dosage*; D003930:Diabetic Retinopathy / Q000601:surgery*; D004008:Diclofenac / Q000008:administration & dosage*; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D017075:Laser Coagulation; D008297:Male; D008875:Middle Aged; D010147:Pain Measurement; D010149:Postoperative Pain / Q000517:prevention & control*; D011446:Prospective Studies; D011795:Surveys and Questionnaires; D016896:Treatment Outcome
D000894:Anti-Inflammatory Agents, Non-Steroidal; D004008:Diclofenac