CNS pharma Flashcards
All opioids cause miosis except
meperidine
Opioid receptors are _____ coupled
inhibitory G protein
Recurrent symptoms of opioid toxicity even after nalaxone administration is due to ____
short half life of nalaxone <1 hour
Opioid poisoning causes hypotension due to ____
opioid induced histamine release
morphine has a vaso___ effect
dilator
Effect of opioid on bladder:
Urinary retention
- block urinary voiding reflexes
- ↑ sphincter tone
- ↑ bladder volume
Long term use of opioid effects?
- receptor downregulation and decoupling of 2nd messenger
- upregulation of excitatory NMDA receptors
this causes tolerance and opioid induced hyperalgesia
If pain control needed in renal failure patients___
fentanyl, hydromorphone
Drugs with ____ solubility in blood = rapid induction and recovery times.
↓
relation of solubility, potency and MAC
Drugs with ↑ solubility in lipids = ↑potency = 1 / MAC
Nitrous oxide (N2O) has ___ blood and lipid solubility
↓
Blood/gas partition coefficient corresponds to ______
Anesthetic with a high blood/gas partition coefficient ____
solubility of anesthetic in blood
are absorbed to a greater extent by blood and have a slower onset of action
Steepness of arterial tension curve depends on ___
partial pressure in blood rises more rapidly with
solubility in blood
less soluble anesthetic, producing steeper curve
AV concentration gradiant influences ______ not _______
rate of induction, not anesthetic potency
Malignant hyperthermia is inherited as
autosomal dominant with variable penetrance
d/d of Malignant hyperthermia:
Thyroid storm precipitated by surgery → hyperpyrexia but donot cause sustained muscle contraction
Etomidate:
MOA:
adverse effect:
avoided in:
GABA agonist
inhibits cortisol synthesis
Septic shock
Malignant hyperthermia abnormalities in serum
↑K+, ↑CK, acute hypercarbia
All inhalation anesthetics except ____ cause respiratory depression
nitrous oxide
_______ and ______ have bronchodilation properties and are preferred in patients with asthma.
Halothane and sevoflurane
Order of loss with local anesthetic
(1) pain, (2) temperature, (3) touch, (4) pressure.
Depolarizing neuromuscular blocking drugs Complications include:
hypercalcemia, hyperkalemia, malignant hyperthermia.
Duration of action of succinylcholine is _____
Increased in?
<10 mins
Pseudocholinesterase deficiency: genetic polymorphism in BCHE gene
heterozygote: double time
homozygote: several hours
succinylcholine is metabolized by ____
Pseudocholinesterase
Nicotinic ACh receptor is a non-selective cation channel which allows:
influx of Na+, Ca++
efflux of K+
Atracurium metabolism:
metabolized to laudanosine
spontaneously degrades in plasma and organ tissue → “Hofmann elimination”
Cyclobenzaprine Structurally related to:
Side effects:
TCAs.
May cause anticholinergic side effects, sedation.
Carbidopa, a peripheral DOPA decarboxylase inhibitor, is given with L-DOPA to ______ of L-DOPA in the brain and to limit ______
↑ bioavailability
peripheral side effects.
Initial treatment of Parkinson disease
SAC
selegiline
amantidine
anti-Cholinergic
how to treat CNS effects of L-dopa/Carbidopa if decreasing dose donot work
Atypical antipsychotic i.e. Clozapine
