Benzodiazepines Flashcards
1
Q
Benzodiazepine names
A
Diazepam- long acting (>24 hours)
Oxazepam- short acting (6-10 hours)
Midazolam- ultra-short (4 hours)
2
Q
Benzodiazepine effects
A
Hypnotic Amnesic Muscle relaxant Anticonvulsant Anxiolytic Appetite stimulant
3
Q
Hypnotic Effects
A
Dec. Latency of sleep Dec. Awakenings Dec. REM sleep Dec. Stage 3 & 4 NREM Inc. Stage 2 NREM Inc. Total sleep time
4
Q
Antidote- Benzodiazepine receptor antagonist
A
Flumazenil (may precipitate withdrawal seizures) T1/2: 0.7-3 hours Rapid hepatic clearance Agitation and confusion Diziness and dyspnoea Controversial in overdose
5
Q
Method of Action
A
Binds alpha1 sub-unit at GABAa (relaxant and anxiolytic at alpha2)
Increases frequency of opening and decrease inactivation
Increases Cl- transport causing hyperpolerisation
6
Q
Side Effects
A
Addiction (especially with midazolam) Physical dependence/ tolerance (GABAa downregulation) Withdrawal: (tremors, anxiety, seizures, psychosis) Sedation and diminished judgment Anterograde amnesia Confusion & disorientation Central ataxia- falls Elderly are sensitive
7
Q
Pharmacokinetics
A
Metabolised rapidly by liver (long acting give active metabolites) Should not be co-administered with other depressants including alcohol and class 1 antihistamines
8
Q
Use
A
Psychomotor agitation in alcohol withdrawal (long acting usually, short acting with hepatic impairment)
IV usage for seizures- especially status epilepticus
Anaesthesia
Conscious Sedation
Insomnia and parasomnia in children
Muscle relaxants- MS, Stroke, trauma, tetanus: also cause sedation
Acute anxiety states
