University:
Western Sydney University
Course:
MEDI 2003 | Clinical Sciences 2
Academic year:

2024
Views:

342

Pages:

2
Author:

Mariam A.

Anxiety disorders      Generalised anxiety disorder: ongoing state of excessive anxiety lacking any clear reason or focus. Panic disorder: sudden attacks of overwhelming fear occurring in association with marked somatic symptoms, such as sweating, tachycardia, chest pains, trembling and choking. Phobias: strong fears of specific objects or situations. Post-traumatic stress disorder: anxiety triggered by recall of past stressful experiences. Obsessive compulsive disorder: compulsive ritualistic behaviour driven by irrational anxiety. Causes  Genetics.  Change in brain biochemistry (serotonin and GABA).  Overactive fight-flight response.  Stressful life circumstances.  Learned behaviour. GABAergic system  The GABA-A receptor is an oligomeric glycoprotein.  Binding of GABA causes the channel to open and Cl- to flow into the cell with the resultant membrane hyperpolarisation, leading to inhibition of the signal. Anxiolytics  Benzodiazepines (BZDs).  Barbiturates (BARBs).  Others: o 5-HT1A (serotonin) receptor agonists. o 5-HT2A, 5-HT2C and 5-HT3 receptor antagonists. o SSRIs. Mechanism of action  Benzodiazepines: increase frequency of openings of GABA channels.  Barbiturates: increase opening time of GABA channels.  Both: increase receptor affinity for GABA. Properties of benzodiazepines  Wide margin of safety if used for short periods; prolonged use may cause dependence.  Have little effect on respiratory or cardiovascular function compared to barbiturates and other sedative hypnotics.  They are often used to calm down patients before major surgery. Side effects of benzodiazepines  Related primarily to CNS depression and include: o Drowsiness, excess sedation.   o Impaired coordination. o Nausea, vomiting. o Confusion, memory loss. Dependence with these drugs may develop. Serious withdrawal syndromes can include convulsions and death.