Phenobarbitone is an anti-seizure medication that can be used to treat epilepsy, as well as to relieve anxiety and tension in certain situations. There are several synonyms for phenobarbitone, including phenobarbital, luminal, and phenemal. Some other names for this medication may include phenobarb, barbita, and PB. Phenobarbitone works by slowing down brain activity and calming nerve impulses, which helps to prevent seizures and promote relaxation. It is important to note that while phenobarbitone can be effective in treating various conditions, it can also have side effects and should only be taken under the care of a physician.