Opitone 30 Tablet belongs to a class of medicines called barbiturates. It is used to treat and prevent epilepsy (seizures). They also have hypnotic properties. This means, they slow down the activity of the brain and can make you feel sleepy or dizzy. Opitone 30 Tablet may be taken with or without food. However, it is advised to take it at the same time each day as this helps to maintain a consistent level of medicine in the body. Take this medicine in the dose and duration as advised by your doctor as it may be habit-forming with long-term use. If you have missed a dose, take it as soon as you remember it. Do not skip any doses and finish the full course of treatment even if you feel better. Some common side effects of this medicine include nausea, diarrhea, hyperactivity, depression, confusion, decreased blood pressure, and fatigue. It may also cause dizziness and sleepiness, so do not drive or do anything that requires mental focus until you know how this medicine affects you. Remember to consult your doctor if you notice severe rashes, especially accompanied by fever after taking this medicine. It should be noted that long-term use of this medicine can cause pain in joints also.