CNS Pharm Final Flashcards
Phenytoin
Uses?
MOA?
Kinetics?
Anti epileptic Na+ channel blocker- slows the rate of recovery to the channel resting state. Great for FOCAL and SECONDARILY GENERALIZED seizures, but NOT ABSENCE!
Induces P450, and affects oral contraceptives and a bunch of other stuff.
ZERO order kinetics
Carbamazepine
Uses?
MOA?
Kinetics?
Anti epileptic Na+ channel blocker- slows the rate of recovery to the channel resting state. Great for FOCAL and SECONDARILY GENERALIZED seizures, but NOT ABSENCE!
Induces P450, and affects oral contraceptives and a bunch of other stuff including PHENYTOIN.
T1/2 is about 10-20 hours
1st order kinetics
Ethosuximide
MOA?
Uses?
T-type Ca++ channel blocker. Great for ABSENCE seizures!
1st line for uncomplicated absence seizures.
No GABA inhibition.
Valproic acid
Uses?
MOA?
AE?
Acts on Na+, T-type Ca++, and increases GABA transmission.
Drug of choice for idiopathic generalized, and for absence seizures when ethosuximide isn’t effective. Also an alternate for phenytoin and carbamazepine for focal seizures.
Hepatotoxicity is a major AE—-Tx with L-carnitine
Major teratogen—-spina bifida—-take folate!
Fosphenytoin
Like phenytoin, but more soluble and potent
Lacosamide
Na+ channel blocker. adjunctive therapy for FOCAL seizures, but with less AE.
Gabapentin
MOA?
Uses?
AE?
High voltage Ca++ channel blocker —>decrease in NT release
Used for FOCAL seizures with or without secondary generalization. NOT ABSENCE!
Increase GABA in neural and glial cells, but the anti seizure effect is due to blockage of high voltage Ca++ channels —> decrease in NT release.
Similar to endogenous AAs in structure, so there are very few AE, but its not the most effective, so its not 1st line.
Pregabalin
MOA?
Uses?
AE?
Metabolism?
High voltage Ca++ channel blocker —>decrease in NT release
Used for FOCAL seizures with or without secondary generalization. NOT ABSENCE!
Similar to gabapentin, but it works on more stuff such as Glutamate, NE, Substance P, and calcitonin.
More potent than gabapentin.
Adjunct for FOCAL seizures.
*Metabolized by the kidneys, so its ok for liver problem pts.
Benzodiazepines as anti epileptics
4 drugs
MOA?
Uses?
AE?
Increases affinity of GABA for GABA-A receptors, leading to an increase of Cl-
Diazepam, Lorazepam, and Midazolam to treat acute FOCAL and TONIC/CLONIC seizures.
Clonazepam inhibits T-type Ca++, so it works on ABSENCE, but due to AE, its 4th line…
Vigabatrin
MOA?
Uses?
AE?
GABA analogue irreversibly inhibits GABA transaminase, leading to an increase in GABA. Used for INFANTILE SPASMS and refractory FOCAL epilepsy.
Lots of AE, including bilateral visual field defects and irreversible diffuse atrophy of peripheral retinal nerve fiber layer. —> Pts should get a baseline and routine visual field testing!
Topical anesthetics: TAC
Uses?
Tetracaine, Epi, and Cocaine
Used for suturing small cuts and wounds.
Bupivacaine
Uses?
AE?
Used for epidural, but risk of CARDIOTOXICITY
Ropivacaine
Like bupivicaine, but safer.
levobupivicaine
AE?
Like bupivicaine, but safer. Less cardiotoxicity.
Procaine
Uses?
AE?
Local anesthetic. Used for infiltration anesthesia and dental procedures, and OB.
PABA interferes with sulfa drugs.
Tetracaine
Uses?
Local anesthetic. Spinal and topical uses. High hydrophobicity.
Lidocaine
Uses?
Most commonly used local anesthetic.
Rapid, and lots of uses.
Prilocaine
Uses?
AE?
Similar to lidocaine, but exhibits vasoconstriction. Nice for when epi is contraindicated.
Metabolite may cause methemoglobinemia.
EMLA
What is it?
Eutectic Mixture of Local Anesthetics
Pretty much a combo of lidocaine and prilocaine that is given as a cream or a patch.
MAC
Minimum Alveolar Concentration
Its a pretty useful sub for Pcns, and its the Palv that results in the lightest anesthesia. Defined as the level that elicits a movement response from 50% of pts on skin incision.
Small MAC = high potency
Meyer overton equation
MAC ~ 1.3/λ
λ=oil/gas coefficient
Potency increases with oil solubility
Ventilation limited drugs
Drugs?
How fast?
Slow induction and recovery
Diethyl ether
Enflurane
Isoflurane
Halothane
Perfusion limited drugs
Drugs?
How fast?
Fast induction and recovery
Nitrous Oxide
Desflurane
Sevoflurane
Balanced anesthesia
N2O + isoflurane
Role of opiates in anesthesia
Used for synergy
Isoflurane
AE?
Most popular inhaled anesthetic.
Somewhat expensive
Potent vasodilator
Airway irritant
Precipitates myocardial ischemia in pts with CAD
Halothane
Uses?
AE?
Partial hepatic metabolism
Cheap
Non-irritant
Great for induction in children and maintenance in adults
AE is malignant hyperthermia
Nitrous Oxide (N2O)
Uses?
AE?
Low potency
Great for outpatient dentistry and as adjunct to other anesthesia
AE is nausea and pneumothorax
Desflurane
Use?
AE?
Irritant, so better for maintenance rather than induction.
Sevoflurane
Use?
Sweet taste, non-irritant
Great for pediatric use.
Atracurium
Non-depoarizing blocker
Isoquinoline
Intermediate acting
Releases histamine at high doses
Cisatracurium
Non-depoarizing blocker
Isoquinoline
Intermediate acting
Most popular muscle relaxant in clinical practice
Uses for pts with impaired renal or hepatic function
Muscle relaxant for Sx and intubation
Gentacurium
Non-depolarizing blocker
Rapid onset with short duration
Few pulmonary effects
3 non-depolarizing blockers, intermediate acting
Vecuronium
Rocuronium
Atracurium
Mecamylamine
Ganglionic blocker used as a possible adjunct to nicotine patch for smoking cessation.
Non-depolarizing blockers: Major pharmacologic properties
Poor GI absorption
No BBB crossing
*Effects are increased by MYASTHENIA GRAVIS, inhaled anesthetics and AMINOGLYCOSIDE antibiotics.
Effects of drugs are reversed by anticholinesterase agents.
Succinylcholine
AE?
Depolarizing blocker
Produces fasciculations followed by sustained muscle paralysis
Short duration- preferred choice for intubation.
No antidote in the case of overdose
May cause hyperkalemia in children and muscle soreness in adults.
May cause malignant hyperthermia
Disulfiram
Use?
MOA?
Tx and prevention of alcoholism
Inhibits aldehyde dehydrogenase —> makes you sick!
Low pt compliance
Naltrexone
Use?
MOA?
Tx and prevention of alcoholism
Mu receptor antagonist —> blocks the DA pathways in the CNS
Acamprosate
Use?
MOA?
Tx and prevention of alcoholism
GABA analogue/ weak antagonist of NMDA
Probably the best drug for this…
Fomepizole
Use?
MOA?
Tx for toxicity of Methanol and Ethylene glycol
Inhibits Alcohol dehydrogenase, induces P450 —> increases own metabolism, so dose increase is needed in 48 hours.
Flumazenil
Use?
MOA?
Tx for BZ or Barbiturate overdose.
GABA-A antagonist
Naloxone
Use?
MOA?
Narcan- Opioid overdose, clinical use
Opioid receptor antagonist
Methadone
Use?
Long acting opioid receptor agonist for the Tx of opioid dependance.
Buprenorphine
Use?
MOA?
Opioid receptor partial agonist for Tx of opioid dependance. Replaces short acting drugs.
Bupropion
Uses?
MOA?
AE?
Nicotine addiction Tx
NE and DA reuptake inhibitor; buffers nicotine craving through noncompetitive antagonist activity at alpha-4-beta-2 and alpha-7
lowers seizure threshold.
Verenicline
Uses?
MOA?
AE?
Nicotine addiction Tx
Partial alpha-4-beta-2 agonist, and full alpha-7 agonist. Use is limited by nausea and insomnia, and is associated with ACUTE PSYCHOSIS and SUICIDAL IDEATION.
