Sedatives and Hypnotics -An Introduction

Sedatives and hypontics are the most desired drugs.

Sedation

Decreased responsiveness to a constant level of stimulation.(Psychomotor retardation)

Reduced excitation, calming and relaxing effect, without excessive drowsiness.

Sedatives

These drugs exert a calming effect and reduce excitement in hyperactive individuals, with little or no effect on motor or mental functions.

Hypnosis

Increased sedation –> increased drowsiness –> induction of state of sleep

Hypnotics

The drugs which produce drowsiness & encourage the onset & maintenance of a state of sleep.

Hypnotics produce drowsiness and facilitate the onset of sleep, resembling normal sleep pattern, causing psychomotor slowing.

Sleep consists of REM and non-REM sleep. REM is for 20-30% of time. 80-100 minute cycle is repeated.

It is further divided into four stages:

Stages of sleep	Wave pattern
Dosing stage	a, b
Patient goes to sleep	a, b theta
Slow wave sleep	Theta, delta, K complexes sleep spindles
Slow wave sleep	Delta (high voltage)

Wave	Frequency	Voltage
Delta	< 4/sec	50 µ v
Theta	4-7/sec	May vary from 0-300 µv
Alpha	8-13/sec
Beta	14-50/sec
K complex	brief high voltage activity
Sleep spindles	10-14/sec	50 µv interspersed with delta wave

The drug should resemble normal sleep pattern. Normal architecture should not be disturbed. Large number of drugs are available.

Actually all drugs are depressants of CNS. Some non-selective, like barbiturates cause non-selective depression of CNS.

Non-selective drugs:

Depress CNS –graded depression
Sedative in small dose,

As dose is increased moderately, there is hypnosis,

Further higher dose produces general anesthesia.

As concentration is further increased, coma or even death may occur.

Dose should not exceed the level of hypnosis.

These drugs are also used for anxiety treatment, thus are anxiolytic drugs. All sedatives relieve anxiety, by causing sedation and drowsiness.

Anxiety

A subjective feeling , fear or apprehension, with or without any obvious cause, usually accompanied by autonomic disturbance, manifested by sympathetic over activity.

Symptoms are of sympathetic over activity.

Mild anxiety is common and needs no treatment. If symptoms become severe, interfering with normal routine of life, only then drugs are prescribed.

These are also known as minor tranquilizers.

Major tranquilizers are called neuroleptics.

Normal anxiety	Pathological anxiety
Anxiolytics	Neuroleptics
Same drug in smaller dose, acts as sedative5mg dose of diazepam to produce anti-anxiety effects and sleep	Higher dose is required

Normal or physiological (Adaptive)

i.e. in interviews, examinations

Insomnia

Loss of sleep, deprivation of sleep. Varying from children (GH secretion) to elderly.

Normal adult requires 6-8 hours sleep.

Causes

– Organic

– Psychologic

– Situational

Insomnia may be:

Transient insomnia

Normal individual undergoing emotional disturbances (family, work, etc.) 1-2 doses of hypnotics are indicated to help cope with situation.

Short term insomnia

Also related to emotional disturbances but may reoccur (psychiological disturbance) subjective to feeling. 5-10 day hypnotic with some missing doses.

As continuous use of hypnotics leads to:

Tolerance
Dependence
Rebound insomnia

Chronic insomnia

Rarely benefited by hypnotics. Routine ingestion of hypnotics may produce mild dependence.

Underlying cause needs to be seen, whether psychiatric problem, depression or pain.

Insomnia secondary to underlying cause has to be treated, if pain analgesic is prescribed along with hypnotic.

Sedatives and hypnotics are not prescribed to children and elderly.

Children

Only sometimes given when someambolism (walking at night) occurs, involving hyperactive situations, night terrors, only if lack of sleep is detrimental.

Elderly

Unjustified use leads to greater risk of person becoming ataxic and confused. May produce rebound insomnia, especially if drug is discontinued suddenly.