The hypothesis of the study is that lidocaine will be as effective as ketorolac in decreasing patient's perception of pain as measured by the 10 point Visual Analogue Scale (VAS). The aim of the study is to compare the safety & efficacy of lidocaine versus ketorolac for acute pain secondary to renal colic in the Emergency Department (ED).

The hypothesis of the study is that lidocaine will be as effective as ketorolac in decreasing patient's perception of pain as measured by the 10 point Visual Analogue Scale (VAS). The aim of the study is to compare the safety & efficacy of lidocaine versus ketorolac for acute pain secondary to renal colic in the Emergency Department (ED). The primary endpoint is patient's perception of pain as described by the use of numeric rating scale (NRS) at 15 minutes after initial study interventions. The secondary endpoints are incidence of adverse events during the study period, patient perception of pain as described by the use of NRS at 0, 5, 15, 30, 45, 60, 75, 90 minutes after initial administration of study interventions, frequency and mean dose of rescue analgesic therapy needed at 0, 5, 15, 30, 45, 60, 75, 90 minutes, incidence of adverse events such as but would not be limited to: dizziness, perioral numbness, nausea, vomiting, arrhythmia [examples could be but are not limited to: atrial fibrillation, ventricular tachycardia, ventricular fibrillation), hypotension (≤90/60 mmHg), flushing, headache, tremors, ear pain, injection site reactions, disorientation, respiratory depression (respiratory rate less than 12bpm), oxygen saturation less than 90%)], the number of bedside ultrasounds for diagnosis conducted, the number of CT scans for diagnosis conducted, result of radiologic imaging (Ultrasound / Computerized Tomography), time to patient discharge from the initiation of study medication/placebo, patient satisfaction of pain control based on a Likert Scale, the number of patients who consumed an adjuvant pain medication for analgesia.

Inclusion Criteria:

• Patients 18 years old and older
• Presenting with acute generalized pain secondary to suspected or confirmed renal colic
• Describes pain to be greater than or equal to 3 out of 10 on the numeric rating scale (NRS)
• Provides informed consent.

Exclusion Criteria:

• Reported/documented allergy to lidocaine OR ketorolac (Toradol) OR morphine, corn, aspirin, ibuprofen
• Patients who are hemodynamically unstable as dictated by the medical resident or attending [(Heart rate not within 60-110bpm); (Respiratory rate not within 12-20 bpm); (Blood pressure not within 90/50 to 180/100); (Oxygen saturation not within 94-100%)]
• Patient with unwillingness to provide informed consent
• Patients with past medical history of cardiovascular disorders (examples include but are not limited to: myocardial infarction, ischemic heart disease, atrial fibrillation, heart blocks, Wolff-Parkinson-White syndrome, slow heart rate, bradycardia, coronary artery disease, QT prolongation)
• Past medical history of: liver dysfunction (ie: cirrhosis), chronic alcohol abuse, gastrointestinal bleed or recent gastrointestinal bleed (within past 5 days), renal dysfunction or disease, seizures (or currently actively receiving treatment for seizures), inflammatory bowel disease (or currently actively receiving treatment for inflammatory bowel disease), hepatitis (or currently actively receiving treatment for hepatitis).
• History of liver transplant
• Currently on dialysis
• Has acute heart, kidney, liver, respiratory failure or trauma
• In altered mental status
• In significant trauma, actively breastfeeding or pregnant
• Has language barriers who are unable to describe pain,
• Weighing at or over 130kg
• Has a blood pressure reading greater than 180/120 mmHg at triage,
• Previously enrolled to the study

This is a double-blind placebo-controlled randomized trial where blinding will be conducted and applied to the study investigator, physicians, and nursing staff providing care to the patient. An independent biostatistician will conduct a statistical analysis with blinded data. Only the pharmacists preparing the study interventions will be unblended to the study treatments. The pharmacists procuring the interventions will not be part of data collection or analysis.