Phenobarbital is a very classic and very old sedative-hypnotic drug, its pharmacological effects are as follows: 1, has a sedative effect, often used for anxiety, irritability, fidgeting when the sedative effect; 2, has a strong hypnotic effect, can be used to treat intractable insomnia; of course, there are now also very, very many new sedative-hypnotic drugs can replace phenobarbital to treat insomnia, so in the clinical The hypnotic effect is not often used clinically; 3, anticonvulsant effect, often used in the central stimulant after eating resulting in convulsions and other diseases resulting in anticonvulsant effect; 4, antiepileptic, phenobarbital is also a classical antiepileptic drugs. In general, this drug is a classic drug is also more traditional old drug, its sedative, hypnotic, anticonvulsant and antiepileptic. There are now very many newer drugs to be more often chosen for application by front-line clinicians.