Tramadol 100 mg White pill is a rectangular, white tablet marked with the number 019 and is known as a controlled drug & medication, a doctor's prescribed drug for controlling moderate to severe pain in most of the patients. Common adverse reactions may involve feeling lightheaded, sleepy, constipated, nauseous, or experiencing headaches. Improper use of tramadol has the potential to result in dependency, excessive dose intake, or fatality, especially if combined with alcohol or other substances that depress the central nervous system.