The effect of fibromyalgia treatment on tinnitus.

OBJECTIVES: We investigated the frequency of tinnitus in fibromyalgia patients and the effect of drugs used for routine fibromyalgia on tinnitus. METHODS: We included 101 diagnosed fibromyalgia patients. After detailed ear nose throat examination, audiometric tests and tinnitus handicap index (THI) were performed. After the tests, routine treatment for fibromyalgia was started by the physical therapy and rehabilitation department. Two months after the beginning of the treatment, THI were repeated again and the results were statistically evaluated. RESULTS: All patients included in the study were women. 74.3% of the patients had tinnitus. Pregabalin and selective serotonin and norepinephrine reuptake inhibitor (SNRI) antidepressant-treated patients were evaluated; In both groups, there was a statistically significant difference between pre- and post-treatment tinnitus levels (p < .001). However, there was no statistically significant difference between pregabalin group and diloxetine group according to treatment results. CONCLUSIONS: The incidence of tinnitus is high in fibromyalgia patients. That pregabalin and duloxetine agents routinely used in fibromyalgia require further experimental and human studies in order to be able to use in tinnitus.

The diuretic effect of urea analog dimethylthiourea in female Wistar rats.

Urea plays an important role in the urinary concentrating mechanism in the kidney by contributing greatly in the generation of hyperosmolar medulla due to the presence of urea transporters, which mediate facilitated transport of urea. In this study, we investigated the possible diuretic effect of urea analog and urea transporter inhibitor, dimethylthiourea (DMTU), in rats. Female Wistar rats were divided into two groups, group 1 (control group, n = 7) rats were injected with saline intraperitoneally (i.p.), while group 2 (DMTU group, n = 7) rats were injected with 500 mg/kg DMTU (i.p.) and an additional dose of 125 mg/kg DMTU after 8 h. DMTU administration induced an approximately three times increase in daily urine volume (p < 0.001) and decreased urine osmolality to approximately 35% of controls (p < 0.0001). DMTU also increased free water clearance (p < 0.0001) without a significant change in osmolar clearance. DMTU treatment caused an increase in urea clearance (p < 0.05) and fractional excretion of urea (p < 0.05) with a decrease in serum urea concentration (p < 0.001). DMTU had no effect on creatinine clearance or serum electrolytes, creatinine levels and osmolality. With these findings, we report for the first time that DMTU has a prominent diuretic effect with increased urea excretion, which may be explained by the inhibitory effect of the drug on urea transporters. Our findings suggest that DMTU may be used as a diuretic agent and also could be used as a lead compound for the development of novel diuretics.