B12 Drugs: Epilepsy And Anaesthesia Flashcards
How does propofol work?
It is an IV general anaesthetic which is administered with the analgesic lidocaine. It can’t be given to children under 3, myocardial depression and causes rhabdomylysis and vomiting.
How does thiopentene sodium work?
It is a barbiturate which is a short acting IV general anaesthetic that is used in induction phase which acts on the GABA-a agonist to prolong opening of channel.
What are the considerations for the use of thiopentene sodium?
It causes cough, respiratory depression and cardiovascular suppression.
It is severely limb threatening if given interatrerially.
How does donepezil work?
It is a reversible acetylcholinesterase inhibitor which is given to increase cholinergic transmission as a treatment of Alzhiemer’s disease.
NB: Should be avoided sick sinus syndrome due to bradycardia. It can cause urinary incontinence.
How does suxamethonium work?
It is a depolarising blocking agent of acetylcholine which over-stimulates action potentials. Should be avoided in malignant hyperthermia and hyperkalemia.
NB: Causes bradycardia and arrythmia.
How does isoflurane work?
Gas anaesthetic which stimulates **inhibitory GABA neurotransmitters and downregulates glutamate. **
NB: Should be avoided in malignant hyperthermia. It can cause apnoea and hypersalivation.
How does Atracurium work?
It is a non-depolarising blocking agent which competitively inhibits acetylcholine.
It should be avoided in neuromuscular disorders and hypothermia. May cause hypotension.
How does fentanyl work?
It is an opioid analgesic on mu receptors for hyperpolarisation which is given for operations and chronic severe pain.
Should be avoided in respiratory depression and raised intracranial depression. It causes apnoea. With short-term use, hypertension occurs. With long term use, hypotension.
What is the NMDA receptor?
Glutamate receptor for Ca+ influx
What is the AMPA receptor?
Glutamate receptor for Na+ influx.
How does phenobarbital work?
It is a barbiturate which is a GABA agonist that is given for epilepsy.
It causes severe respiratory and cardio suppression so should be avoided in children and the elderly, and drug abuse.
NB: Causes hallucinations and agranulocytosis.
How does sodium valproate work?
Inhibits GABA transaminase which metabolises GABA, therefore increases availability of GABA. Should be avoided in girls and women and acute porphyria. It causes alopecia and dizziness.
How does lithium work?
Anti-manic agent which **reduces levels of excitatory neurotransmitters and increases GABA levels. ** As an anti-psychiatric drug, it increases level of triglycerides.
NB: Should be avoided in Addison’s disease and cardiac disease. Causes nephropathy and thyroid damage.
How does diazepam work?
It is a benzodiazepine which is a GABA agonist to reduce neurone excitability. Should be avoided in neuromuscular respiratory weakness and chronic psychosis. Can cause decreased alertness.
How does lamotrigine work?
It ** inhibits voltage gated Na+ channels on voltage gated Ca2+ for release of glutamate on pre-synaptic neurons. ** It can lead to aggression and sleep disorders.
