by Dr. Prashant, MD.
A sedative is drug which produces calmness, reduces excitement.
A hypnotic is a drug which produces /induces sleep.
A sedative given in heigher dose may act as hypnotic.
Both Barbiturates and Benzodiazepines are sdatives and hypnotics.
1- Barbiturates have low therapeutic index, have low safety margin.
Benzodiazepines have high therapeutic index, have hiogher safety margin. Ingestion of even 20 tablets does not endanger life
2-Barbiturates suppress/depress respiratory center. Overdose may lead to respiratory failure, apnea results.
Benzodiazepines do not cause respiratory depression to the extent barbiturates do.
3- Barbiturates suppress/depress vasomotor centre, leading to hypotension.
Benzodiazepines , hypnotic doses do not lead to hypotension.
4-Barbiturates distort normal balance of REM/NREM sleep, leading to hangover.
Benzodiazepines , hypnotic doses cause less hangover.
5-Benzodiazepines overdose can be treated by Flumazenil antidote.
Barbiturate overdose is fatal , no anti dote is available , only forced alkaline diuresis is done to prevent poisoning.
6- Barbituraters are enzyme inducers may lead to failure of drugs like oral contraceptives given cocurrently.