Oxycodone is a semi-synthetic opioid with analgesic activity, which helps relieve pain severe enough to require prescribed treatment. It acts on the central nervous system to modify the way your brain responds to pain. These drugs are available in both controlled-release and immediate-release formulations, which can be taken orally. The onset of pain relief typically begins within 20 minutes and may last up to 6 hours. Some of the common side effects include dizziness, drowsiness, sweating, loss of appetite, and constipation. Before you order oxycodone online, please make sure to consult your doctor for possible drug interactions.