Tramadol is a centrally-acting opioid analgesic used to treat moderate to severe pain. It has a similar structure to codeine but is about 4 times more potent. Tramadol is available in immediate-release and extended-release formulations. It is usually taken orally, but can also be given by injection or rectally. Tramadol 50mg is effective in reducing pain and is generally well-tolerated. However, it can cause side effects such as nausea, vomiting, constipation, dizziness, and drowsiness. Tramadol should be used with caution in patients with a history of seizures, drug abuse, or respiratory problems.