Anxiolytics

Question 1

What are the signs and symptoms of anxiety?

Answer 1

Somatic symptoms:

1. Increased cardiovascular
2. Increased respiratory
3. Decreased Gastrointestinal
4. Increased Genitourinary
5. Cold and Clamy skin
6. Tense musculoskeletal system

Question 2

What are Benzodiazepines

Answer 2

Common class of drugs which are used as anxiolytics or hypnotics

Question 3

What are examples of Benzodiazepines?

Answer 3

Short acting (2-3 hrs): Midazolam
Intermediate Acting (4-8 hrs): Lorazepam, Alprazolam
Long Acting (1 day): Diazepam

Question 4

What is the mechanism of action of Benzodiazepines?

Answer 4

Potentiation of GABA actions by increasing the frequency of chloride channel opening induced by GABA.
Benzodiazepines have specific benzodiazepine sites in the CNS, which is not the same as that of GABA sites.
Chloride is an inhibitory neurotransmitter which enters through these chloride channels/
The cell hence becomes hyperpolarised (more negatively charged)

Question 5

Can one die from overdosing on benzodiazepine?

Answer 5

No. This is because the mechanism of benzodiazepine is still controlled by and dependent on GABA.

Question 6

What is the difference between diazepam and phenobarbital

Answer 6

Diazepam has increased chloride entry frequency but it still closes.
Phenobarbital opens the chloride channel and prolongs its opening duration hence it does not close.

Question 7

What is the route of administration of Benzodiazepines?

Answer 7

Oral: Fast onset of 0.5-1 hr
IV: Immediate onset

Question 8

What are the therapeutic uses of Benzodiazepines?

Answer 8

1. Treatment for anxiety and insomnia
2. Emergency for status epilepticus => epilepsy: IV diazepam, lorazepam
3. Muscle relaxant (eg. tense jaw)
4. Premedication for sedation as part of balanced anaesthesia
5. Alcohol withdrawal

Question 9

What are the adverse effects of Benzodiazepines?

Answer 9

CNS:
Dose-related drowsiness, diminished motor skills, increased reaction time
Anterograde amnesia, Memory disturbances (esp for IV)
CVS:
Reduced BP, Cardiac Arrest (when given IV rapidly)
Paradoxical Effects:
Garrulousness (talking a lot), Irritability, Hallucination, Hypomaniac behaviour
Obstetric:
Neonatal Toxicity - Floppy child syndrome (No muscle tone)
Tolerance, Dependance, Withdrawal

Question 10

Can benzodiazepines be used in pregnancy?

Answer 10

no. it can cross the placenta barrier