The analgesic effect of diclofenac sodium administered via the epidural route in an experimental visceral pain model.
OBJECTIVE
The aim of this study was to investigate the characteristics of the analgesic effect of diclofenac sodium injected epidurally in single or repeated doses and whether tolerance develops in long-term use.


METHODS
A total of 30 rats were included in the study. The rats were anesthetized using intraperitoneal ketamine hydrochloride and an epidural catheter (EC) was inserted at the level of 13th dorsal thoraco-lumbar vertebrae (T13). Eleven rats were excluded from the study. The remaining 19 rats were randomly divided into three groups; Group Control (Group C) (n = 6) received 20 μL normal saline solution (NS) via EC for 10 days; Group Single Dose (Group SD) (n = 6) received 20 μL NS for 9 days and 6 μg diclofenac via EC on 10th day; Group Ten Doses (Group TDs) (n = 7) received 6 μg diclofenac via EC in 20 μL NS for 10 days. On the 10th day, 30 min after epidural diclofenac sodium, 300 mg/kg of 3% acetic acid was injected via intraperitoneal route, and the rats were observed for 30 min and number of writhing reflex (WR) was recorded.


RESULTS
The values of total number of Writhing Reflex (WRT) and Writhing reflex per minute(WR/min) were found to be significantly higher in Group C compared with Groups SD and TD (P = 0.009).


CONCLUSIONS
Single and repeated doses of diclofenac sodium via epidural route have an analgesic effect in a visceral pain model in rats without developing tolerance.
Department of Anesthesiology, Ankara Numune Training and Research Hospital, Ankara, Türkiye.
O
O
Kilci
Department of Anesthesiology, Turkish Ministry of Health Mersin State Hospital, Mersin, Türkiye.
T
T
Demir
Department of Anesthesiology, Turkish Ministry of Health Ataturk State Hospital, Ankara, Türkiye.
M
M
Günbey
Department of Neurosurgery, Ankara Kecioren Hospital, Ankara, Türkiye.
C
C
Kara
Department of Anesthesiology, Gazi University Faculty of Medicine, Ankara, Türkiye.
D
D
Bayazit
Department of Anesthesiology, Ankara Numune Training and Research Hospital, Ankara, Türkiye.
D
D
Ornek
Department of Anesthesiology, Ankara Numune Training and Research Hospital, Ankara, Türkiye.
M
M
Baydar
D019342:Acetic Acid / Q000633:toxicity; D015360:Analgesia, Epidural / Q000379:methods*; D000818:Animals; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000008:administration & dosage* / Q000494:pharmacology; D001522:Behavior, Animal / Q000187:drug effects; D004008:Diclofenac / Q000008:administration & dosage* / Q000494:pharmacology; D007274:Injections, Intraperitoneal; D008297:Male; D010147:Pain Measurement; D010149:Postoperative Pain / Q000188:drug therapy; D011897:Random Allocation; D051381:Rats; D017207:Rats, Sprague-Dawley; D059265:Visceral Pain / Q000139:chemically induced / Q000188:drug therapy*
D000894:Anti-Inflammatory Agents, Non-Steroidal; D004008:Diclofenac; D019342:Acetic Acid