Uroselective Alpha-1-Antagonist to Reduce the Incidence and Duration of Postoperative Urinary Retention Following Spine Surgery

Inclusion Criteria: * Cervical Laminectomy * Cervical Posterior Fusion * Cervical Anterior/Posterior Fusion * Lumbar Laminectomy * Lumbar Posterolateral Fusion * Lumbar Interbody Fusion Exclusion Criteria: * Cervical Anterior Discectomy and Fusion * Cervical Anterior Corpectomy * Cervical Posterior Discectomy * Cervical Foraminotomy * Lumbar Discectomy (METRx or Open) * Lumbar Foraminotomy * Lumbar Anterior Fusion * Myelopathy with bladder dysfunction * Patients currently taking an alpha-antagonist o The following drugs are alpha antagonists: alfuzosin, doxazosin, prazosin, terazosin, tamsulosin, and phenoxybenzamine. * Patients with history of allergy or sensitivity to tamsulosin or other alpha-antagonist * History of prostatectomy or urologic surgery involving the bladder or urethra * Severe liver disease or end-stage renal disease * Patients taking strong inhibitors of CYP3A4 o The following drugs are strong inhibitors of CYP3A4: ketoconazole, itraconazole, clarithromycin, ritonavir, indinavir/ritonavir, lopinavir/ritonavir, and conivaptan. * Mental disability or prisoner * Pregnancy (for anesthesia purposes)