Soleimanpour et al. Journal of Medical Case Reports 2011, 5:256 http://www.jmedicalcasereports.com/content/5/1/256 C A S E R E P O R T JOURNAL OF MEDICAL CASE REPORTS Open Access Parenteral lidocaine for treatment of intractable renal colic: a case series Hassan Soleimanpour1*, Kamaleddin Hassanzadeh2, Dawood Agha Mohammadi3, Hassan Vaezi1 and Robab Mehdizadeh Esfanjani4 Abstract Introduction: We report a case series of successful treatment of intractable renal colic using parenteral lidocaine. Case presentation: Because of inconsistent responses to standard treatment with opioids and non-steroidal anti- inflammatory drugs in patients with renal colic pain, we decided to begin a trial of a single intravenous dose of lidocaine (approximately 1.5 mg/kg) slowly in eight patients with intractable renal colic who were referred to our emergency medicine department. The patients were six men and two women with a mean age at diagnosis of 34.62 years (age range, 28 to 42 years). The patients were of Iranian ethnic origin. The patients’ degree of pain, based on Visual Analog Scale score upon entering our emergency medicine department, was recorded 10, 20, and 30 minutes after lidocaine injection. The patients’ degree of pain decreased from a mean Visual Analog Scale score (±SD) of 8.87 ± 0.99 (95% confidence interval (95% CI) 8.04 to 9.70) to a mean Visual Analog Scale score (±SD) of 1 ± 2.82 (95% CI -1.36 to 3.36) before and 30 minutes after lidocaine treatment, respectively. Two of eight patients experienced transient mild dizziness, and three of eight patients experienced minimal slurring of speech. No patient experienced serious adverse events. Conclusion: Parenteral lidocaine treatment can reduce pain dramatically or subtly. Introduction Numerous medications have been utilized for pain relief in patients with renal colic; however, no medication has yet been found to relieve pain quickly and completely. A variety of drugs are used to treat this condition, includ- ing anti-spasmodics, non-steroidal anti-inflammatory drugs (NSAIDs), and opioids [1]. Parenteral lidocaine has been reported to be effective in small studies of var- ious neuropathic pain conditions, including diabetic neuropathy, post-operative pain, post-herpetic neuralgia, centrally mediated pain, headache, and malignant nerve infiltration [2-5]. Case presentation Eight patients (mean age (±SD) 34.62 ± 4.34 years, six men and two women) with intractable renal colic who pre- sented to our emergency department were enrolled into this study. All included patients previously underwent * Correspondence: h_mofid1357@yahoo.com 1Emergency Medicine Department, Tabriz University of Medical Sciences, Daneshgah Street, Tabriz 51664, Iran Full list of author information is available at the end of the article therapy with morphine and NSAIDs previously but were resistant to treatment. Adults with acute flank pain radiat- ing to the groin, vomiting, and urinary symptoms were eli- gible for inclusion in the study. Every aspect of the present study was explained to the patients, and we obtained their written consent for participation in the study. The diagno- sis of renal stone was confimed by ultrasonsgraphy and by the presence of red blood cells (RBCs) revealed by urinaly- sis [6,7]. Because of patients’ inconsistent responses to standard treatment with opioids and NSAIDs for renal colic pain, the decision was made to begin a trial of a sin- gle, slowly administered intravenous dose of lidocaine (approximately 1.5 mg/kg) for these patients. As fluid ther- apy is not commonly used in our center to treat patients with renal colic and is used only for patients who are dehydrated or have sepsis, our patients received very little fluid (10 mL) administered only by injection [8]. The mean pain degree reported by our patients was recorded based on Visual Analog Scale (VAS) score before and 10, 20, and 30 minutes after injection (Table 1). The mean VAS scores (±SD) decreased from 8.87 ± 0.99 (95% confi- dence interval (95% CI) 8.04 to 9.70) to 1 ± 2.82 (95% CI © 2011 Soleimanpour et al; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.