The effect of photobiomodulation therapy on the management of chronic idiopathic large-bowel diarrhea in dogs.

To evaluate photobiomodulation therapy's effectiveness (PBMT) in managing chronic idiopathic large-bowel diarrhea. Thirty dogs were selected and divided into a control (CG) and treatment group (TG). CG received psyllium husk at the dose of 4 tablespoons/day for 30 days. TG received PBMT with a Class IV therapeutic laser, divided into three sessions on week 1, two sessions on week 2, and one session on week 3. A daily log of fecal characteristics was maintained, and on days 0, 8, 15, and 30, a canine inflammatory bowel disease index (CIBDAI) and body condition scores (BCS) were obtained. Results were compared using a Mann-Whitney test. Multiple regression was run to predict CIBDAI, Bristol stool scores, and diarrhea from different parameters. The Kaplan-Meier test was used to compare the occurrence rate of ≥ 1 day of diarrhea and ≥ 2 days of diarrhea by 30 days. Cox regression analysis to investigate interest covariates influences the same outcome. A p < 0.05 was set. The sample included 15 Belgian Malinois Shepherd Dogs, 10 German Shepherd Dogs, and 5 Dutch Shepherd Dog, with a mean age of 3.6 ± 2.3 years and a bodyweight of 24.6 ± 8.0 kg. TG showed an improvement in all scores and clinical signs, increased body weight, and BCS. An increased time of appearance of a second episode of diarrhea was observed in both groups. Activity level contributed to the prediction of defecation frequency and CIBDAI. PBMT significantly improved clinical signs and frequency of diarrhea episodes compared to psyllium husk.