Drug Interaction Report

Promethazine may reduce the effectiveness of opicapone. In addition, using these medications together may increase the risk and/or severity of side effects like drowsiness, low blood pressure, dizziness, and lightheadedness. These effects may occur with either medication alone and are most likely to be seen at the beginning of treatment, following a dose increase, or when treatment is restarted after an interruption. Let your doctor know if you develop these symptoms and they do not go away after a few days or they become troublesome. Avoid driving or operating hazardous machinery until you know how the medications affect you, and use caution when getting up from a sitting or lying position. It is important to tell your doctor about all other medications you use, including vitamins and herbs. Do not stop using any medications without first talking to your doctor.

Food may delay and reduce the absorption of opicapone, which may lead to lower blood levels of the medication and possibly reduced effectiveness. You should take opicapone once daily at bedtime. Do not eat food for at least 1 hour before and at least 1 hour after taking opicapone. Talk to your doctor or pharmacist if you have any questions or concerns.

Ask your doctor before using promethazine together with ethanol (alcohol). This can cause uncontrollable movements, agitation, seizures, severe dizziness or fainting, coma, very deep sleep, irregular heartbeats, and high or low body temperature. Use caution when driving, operating machinery, or performing other hazardous activities, these medicaions may cause dizziness or drowsiness. If you experience dizziness or drowsiness, avoid these activities. It is important to tell your doctor about all other medications you use, including vitamins and herbs. Do not stop using any medications without first talking to your doctor.