• What does anterograde amnesia mean and which drugs can cause this effect?

Anterograde amnesia is the inability to remember the memories and happenings during the time of use of a drug, leading to a partial or complete inability to recall the recent past. This disorder is  usually caused by benzodiazepine drugs such as midazolam, lorazepam and diazepam. 

• Name the effects of the sedative-hypnotic drugs on the normal sleep pattern and explain their significance to the patient.

Benzodiazepines reduce the time to fall asleep and increase the total sleep time. It increases the duration of phase 2 Non rapid eye movement (NREM) sleep and Benzodiazepines also have a small reducing effect on Rapid eye movement (REM) sleep. 

High doses of BD's reduce REM sleep and Benzodiazepines reduce the duration of phase 4 NREM. Tolerance effects can occur on sleep patterns after 1-2 weeks of using hypnotics. Gradual withdrawal is recommended so that side effects such as nightmares and relapsing insomnia can be avoided.

Short-acting BDs is used in patients who have difficulty falling asleep, such as Midasolam or Triasolam

Intermediate BDs is used in patients who wake up early in the morning. 

Long-acting BDs helps the control of anxiety.

• Which of the sedative-hypnotic drugs are used as a supplementary therapy in anaesthesia?  Can you explain why?

Barbiturates and Benzodiazepines such as Midazolam, Diazepam and Lorazepam.

These drugs are used as adjunctive therapy in anesthesia, because they often cause anterograde amnesia. That is, if a patient were to wake up, during or after an operation, the patient would not remember the events.

• Which of the sedative-hypnotic drugs are used as anticonvulsants?

Phenobarbitone coupled with a benzodiazepine, thiopentone, nitrazepam, clobazam, clonazepam.

• What is the mechanism of the muscle-relaxing effects of some of the carbamates and the BDs?

Muscle-relaxing effects occur because the drugs inhibit the polysynaptic reflexes.

• Discuss the effects of the sedative-hypnotic drugs on the respiratory and cardiovascular systems.

Sedative-hypnotic drugs cause respiratory depression in a person who has a pulmonary disease and can also cause cardiovascular suppression in a patient who has a cardiovascular disease. Therefore, this effect should be considered especially in the case of intravenous administration because the effects may then be more dangerous.