Hi & Welcome. You have read it right. It may cause harmful interactions. Avoid taking these medications together. Fioricet is a combination (Acetaminophen, Butalbital, & Caffeine) medication used to treat tension headaches that are caused by muscle contractions. It is also used to treat fever. Caffeine is a central nervous system stimulant. It relaxes muscle contractions in blood vessels to improve blood flow. Butalbital (barbiturate) is a sedative that helps to decrease anxiety and cause sleepiness and relaxation. Taking Metoclopramide together with Butalbital may increase side effects such as dizziness, drowsiness, confusion, and difficulty concentrating. It may also cause impairment in thinking, judgment, and motor coordination. Activities requiring mental alertness such as swimming, driving or operating hazardous machinery should be avoided if you wish to continue to take the medications together. Hope to have answered your query.