Benzodiazepines Flashcards
Give 4 examples of benzodiazepines?
- Diazepam
- Temazepam
- Lorazepam
- Chlordiazepoxide
What is the mechanism of action of benzodiazepines?
Increase affinity of inhibitory neurotransmitter GABA to bind to GABAa receptor, causing post-synaptic chloride ion channels to open
What are the routes of delivery of benzodiazepines?
- PO
- IM
- IV
- Buccal
- PR
What must be available when administered IV benzodiazepine?
Resuscitation facilities
What are the indications for benzodiazepines? -
- Treatment of seizures and status epilepticus
- Short-term treatment for severe, distressing, or disabling anxiety
- Short-term treatment for insomnia
- Procedural sedation
What are the indications specifically for chlordiazepoxide?
Alcohol withdrawal
What are the indications specifically for diazepam?
- Tetanus
- Muscle spasm
- Acute drug-induced dystonic reactions
What are the contraindications to benzodiazepines?
- Respiratory depression
- Respiratory failure
- Neuromuscular conditions, e.g. unstable myasthenia gravis
Why are benzodiazepines contraindicated in respiratory depression/failure and neuromuscular conditions?
In overdose, they can cause a loss of airway reflexes, which can lead to airway obstruction, and patients with respiratory depression or neuromuscular problems are at increased risk
When should benzodiazepines be avoided?
Liver failure
Why should benzodiazepines be avoided in liver failure?
Risk of provoking hepatic encephalopathy
Can you use benzodiazepines in elderly?
Avoid if possible, or consider lower doses
What monitoring is required with benzodiazepines?
- Monitor vital signs and clinical state frequently when administering drug IV or in high oral doses
- Ask about symptoms and side effects when reviewing patients who take benzodiazepines in the community
What might interact with benzodiazepines?
- CYP450 inhibitors
- Alcohol and opioids
- Antihypertensive medications
- Clozapine
- Flumazenil
What might happen if benzodiazepines are given with CYP40 inhibitors?
Increased effects of benzodiazepines
What might happen if benzodiazepines are given with alcohol or opioids?
Increased sedative effects
What might happen if benzodiazepines are given with antihypertensive medications?
increased hypotensive effects
What might happen if benzodiazepines are given with clozapine?
Increased CNS depression
Why should flumazenil not be administered following the use of diazepam to treat seizures?
Due to risk of intractable seizures
What are the common side effects of benzodiazepines?
- Amnesia, confusion, and drowsiness
- Ataxia and muscle weakness
- Dependence
What are the uncommon side effects of benzodiazepines?
- GI disturbances
- Visual disturbances, headaches, dizziness, tremor, dysarthria
- Changes in libido
- Gynaecomastia
What are the rare/frequency not known side effects of benzodiazepines?
- Apnoea
- Respiratory depression
- Blood disorders
- Jaundice
- Hypotension
- Hallucinations
- Changes in mood and behaviour
What patient counselling is required with benzodiazepines?
- For short term use only
- Impairment of normal activities
- Withdrawal effects
- Stop alcohol consumption whilst on chlordiazepoxide
What should the patient be told about short-term use with benzodiazepines?
Inform them that benzodiazepines are a short term treatment and not a long term solution to their problems, and that they are highly addictive. They should not be taken for more than 4 weeks, and should not be taken every day
What should the patient be told about impairment of normal activities with benzodiazepines?
Warn patient that drug can cause drowsiness that may impair their ability to drive or operate machinery. Patients who receive benzodiazepines for procedural sedation should be informed they should not drive afterwards
What should the patient be told about withdrawal effects of benzodiazepines?
Very addictive, and can cause withdrawal symptoms when they are stopped
