The Effect of Topical Local Anesthetics on Thermal Pain Sensitivity in Patients with Irritable Bowel Syndrome

Table 4

Average thermode temperatures (±SD) of prolonged painful stimulus at a fixed intensity rating between IBS and control participants (Trial 1). The baseline session represents data collapsed across sessions 2, 5, and 7. Participants rated a continuous thermal stimulus to induce 10% and 25% pain intensities during the induction phase and sustain 25% pain intensity during the maintenance phase for the various testing sessions with (rectal: rectal lidocaine + oral placebo; oral: rectal placebo + oral lidocaine) and without (placebo: rectal placebo + oral placebo) application of lidocaine.

	IBS				CONTROL
	Baseline	Placebo	Rectal	Oral	Baseline	Placebo	Rectal	Oral
Induction
10% (°C)	43.6 (2.4)	44.2 (2.1)	43.9 (2.7)	44.7 (2.7)	45.8 (1.9)	46.5 (2.2)	46.3 (1.8)	46.6 (1.2)
25% (°C)	44.2 (2.4)	44.1 (2.4)	46.3 (1.8)	44.2 (2.8)	46.6 (1.7)	46.6 (2.5)	46.4 (1.9)	46.8 (1.4)
Maintenance
25% (°C)	45.5 (1.8)	44.8 (2.3)	45.8 (1.7)	45.8 (2.0)	47.3 (1.7)	47.0 (1.9)	47.3 (2.2)	47.7 (1.7)